|12 p.m.||Klebold and Harris leave the cafeteria and go upstairs to the library.
The command post tells dispatch to request Channel 7's news helicopter flying overhead to land in Clement Park in order to pick up a Sheriff's deputy for an aerial survey of the school.
An armored vehicle is requested to rescue the injured because the scene is "not safe for medical."
Uninterrupted media coverage about the shooting in progress at Columbine High School begins on local television channels.
|12:02 p.m.||SWAT commands use of a Littleton fire truck to provide cover as the first Jefferson County, Littleton and Denver SWAT officers approach the school. Deputy Del Kleinschmidt, a Jefferson County K-9 team member assigned to SWAT, volunteers to drive the truck.|
|12:03 p.m.||A television reporter interviews the mother of a student who told her about gunmen dressed in black in the high school's commons area. The station also reports that, according to information gleaned from its police scanners, the school is being evacuated.|
|Littleton Fire Department paramedics rescue Sean Graves, Lance Kirklin and Anne Marie Hochhalter as they lay wounded outside the cafeteria. Because the scene is not safe, law enforcement deputies and officers move in closer to provide cover for paramedics Mark Gorman, Monte Fleming and John Aylward and emergency medical technician Jerry LoSasso as they retrieve the victims.
Gunfire erupts from the second story library windows above the cafeteria as the paramedics rescue the wounded students outside.
Deputy Walker sees a muzzle flash from a library window and returns fire.
Deputy Gardner fires three shots at the gunmen.
Denver police officers also provide suppression fire to the library windows. This allows the paramedics to retrieve the three wounded teens. The fourth student, Dan Rohrbough, is determined to be deceased. The paramedics rush the living to medical attention.
After the ambulances leave the scene with the wounded, the gunfire coming from the library windows ceases. No gunshots attributed to the gunmen are heard again.
Gardner turns his attention to a group of 15 students huddled behind a vehicle in the parking lot just a car away from him. One at a time, he evacuates the students down the line of cars to the protection of the last car farthest away from the school and the shooters.
Other students begin to escape, some out a side door of the cafeteria, and the officers "leapfrog" them back to Gardner or other waiting deputies.
A television news helicopter begins broadcasting aerial images of Columbine High School.
Jefferson County crime lab is en route to the scene with its mobile crime laboratory unit.
|12:06 p.m.||The first SWAT team, on foot behind a Littleton fire truck, arrives at the east main entrance to the school. Manwaring, leading the ad hoc team, splits the group into two teams and directs Jefferson County SWAT Deputy Allen Simmons to take his team into the school. It is estimated that at 12:06 p.m., Simmons' team of five officers enters Columbine High School through the southeast doors. Manwaring will lead the second team, using the fire truck as a shield, to the west side where students are reported "down" and gunfire occurring.
Television news coverage broadcasts images of the SWAT team outside the high school.
Student Anne Marie Hochhalter is transported to Swedish Medical Hospital.
Dispatch advises that a victim shot in the head is at the Caley/Yukon triage area.
|12:07 p.m.||Deputy Walker asks dispatch to check on the status of the party on the roof.|
|12:08 p.m.||Shortly after that last gunshot is fired from the library window at law enforcement and paramedics, Harris and Klebold kill themselves.|
|12:10 p.m.||Medical triage is officially established at Yukon Street and Caley Avenue southwest of the school at the south entrance to Clement Park. Law enforcement had already transported numerous students to the area as they were evacuated from the school's south and west sides. One patient is transported by Air Life and several are transported by ambulance from this area. A second triage and treatment area is set up on the east side of the school after the command post is informed the remaining victims will be brought from inside the school out the east side.|
|12:11 p.m.||The heating and air conditioning repairman, initially thought to be a possible sniper, is removed from the roof.|
|12:12 p.m.||A television reporter positioned at the Yukon and Caley triage area describes the scene as a "very bad situation." He tells the television audience that four or five students are currently being treated and some are bleeding extensively.
Sean Graves, critically injured outside the cafeteria, is transported to Swedish Medical.
|12:14 p.m.||Dispatch tells the command post that a dispatcher is still on the line with students who say that there are suspects in "Rooms 1, 2 and 3" and several parties are shot, including one faculty member.
The Jefferson County, Denver and Arapahoe County bomb squads begin to arrive and stage in the parking lot at Clement Park north of the school. As the incident progresses, bomb technicians from Littleton Fire, Bureau of Alcohol, Tobacco and Firearms (ATF) and the Federal Bureau of Investigation (FBI) join the initial bomb squads. A total of 16 bomb technicians share in the initial response, some sent to evaluate the construction of the divisionary device, others sent to the homes of the suspects, still others providing safety information to the responders, and many later entering the school to deactivate and/or remove the explosives.
|12:15 p.m.||Sgt. Hy, at the command post on Pierce, reports a possible shooter and hostages at the front door of the school.
Moments later a lone student comes out of the main doors and runs to the fire truck. The teen is quickly checked for weapons and injuries, then picked up and put in the back end of the truck's cab. The boy reports that no other people are in the office area.
A news helicopter lands at Clement Park. Jefferson County Sheriff's Sgt. Phil Domenico is put on board and uses the helicopter's camera system to survey the school's roof. He remains in the helicopter for the next several hours surveying the area.
The Jefferson County administrator, emergency management coordinator and public information officer arrive at the Sheriff's Dispatch Center to offer assistance. They soon are asked to help field the escalating media calls as the word of the Columbine shootings begins to spread worldwide. County Commissioners Pat Holloway and Rick Sheehan arrive at the dispatch center soon after the county staff.
The Victim Services Unit of the Jefferson County Sheriff's Office reports to the command post. Personnel are assigned to Columbine Public Library to provide services to the students and parents collecting there. By 12:45, additional counselors and volunteers respond to Leawood Elementary School where high school students and parents are also gathering.
|12:17 p.m.||Deputy Byerly reports that a male wearing a white shirt and black pants is walking on the west side of the school. The young man had heard of the shooting on TV and ran through Clement Park towards the school carrying an unloaded .22 Caliber rifle and a knife in order to "help the police." He subsequently is contacted at gunpoint. Deputies determine that the individual is not involved in the incident.|
|12:18 p.m.||Medical personnel at the Yukon/Caley triage area report four critical, four serious and three stable patients and request 10 ambulances and one helicopter.|
|12:19 p.m.||Deputy Walker reports that he has six students with him.|
|12:20 p.m.||A student being interviewed on air by a television reporter says that the gunmen shot one of his friends. He recognizes the shooters as Columbine students and members of the "Trench Coat Mafia" but does not know their names. He also reports that there may be two or three shooters and they have pipe bombs, sawed-off shotguns, and automatics.|
|12:21 p.m.||Lance Kirklin, shot outside the cafeteria during the first few minutes of the shooting rampage, is transported to Denver Health Medical.|
|12:22 p.m.||The Air Life helicopter lands in Clement Park in preparation to transport critically wounded to area hospitals.|
|12:23 p.m.||Dispatch reports that all cellular lines are busy and it is unable to call the command post.|
|12:25 p.m.||Mark Taylor is transported to University Hospital. Mark was injured outside as he and a group of friends sat on the grassy hill to the west of the stairs where Klebold and Harris first began their shooting rampage.
Dispatch advises that parents are to go to Leawood Elementary School. Law enforcement and victim advocates will assist in coordinating the reunion of parents and children at the elementary school.
|12:26 p.m.||Mike Johnson is transported to St. Anthony's Hospital. Mike was shot as he fled the grassy hill to the west of where Klebold and Harris first began shooting.
The news reports that there are possibly two gunmen and eight victims at Columbine High School.
|12:27 p.m.||Jeanna Park is transported to Denver Health Medical. Kacey Ruegsegger is transported to St. Anthony's. Both girls had been injured by gunfire in the library. All of those who escaped the library ran out of the emergency exit next to the west entrance to the school. They ran to Deputy Taborsky's patrol vehicle and hid behind it until Deputy Searle and several Denver officers were able to load the students in their vehicles. The officers then transported the students either to Deputy Schwieterman at the shed by the ballfields or directly to triage.|
|12:28 p.m.||Aided by the local news stations, the Jefferson County School District announces a parent hotline number for parents of Columbine students.|
|12:30 p.m.||The Jefferson County SORT team (Special Operations Response Team) is paged. The SORT team, which deals primarily with jail disturbances and crowd control, will respond to Leawood Elementary School where students are being evacuated, and parents and media will soon be collecting.
An officer from the Salvation Army arrives and immediately calls in a mobile kitchen, which sets up near the command post to provide water and nourishment for those at the scene. By 1:30 p.m., the Red Cross has staffed its mass feeding vehicle and sends it to the command post and nearby Clement Park where media, students and families are gathering.
|12:31 p.m.||Lt. Manwaring reports that his SWAT team is on the north side of the school with the fire truck, working its way toward the west side.
Valeen Schnurr is transported to Swedish Medical with gunshot wounds. Valeen was in the library at the time of her injuries and was able to escape through the library's emergency exit when Klebold and Harris left the library.
|Manwaring's SWAT team reports that it is now on the west side at the back entrance, upper level.
The first objective of Manwaring's team is to rescue two students lying in front of the west doors. Using the fire truck as a shield, the team of Jefferson County and Denver SWAT officers inch the truck as close to the west doors as possible.
Two Denver SWAT members rescue student Richard Castaldo from the area in front of the west doors and lay him on the bumper of the fire truck.
Jefferson County Deputy Scott Taborsky puts Richard in his patrol car and rushes him to medical assistance.
The SWAT team makes a second approach to the area outside the west doors, this time to retrieve Rachel Scott. They bring Rachel to the fire truck and determine that she has already died.
The team makes a third approach, this time in an attempt to rescue the boy at the bottom of the stairs. They return without him, acknowledging that Daniel Rohrbough is deceased.
|12:39 p.m.||Dispatch announces that the Jefferson County Sheriff's mobile command bus is on scene and activated.
Manwaring's SWAT team requests a floor plan of the school.
|12:40 p.m.||Dan Steepleton is transported to Littleton Hospital.
Information is received that a natural gas leak is occurring in the school. A decision is made to have Public Service Company shut off the gas as soon as it is considered safe to approach the main valve. A crew from PSC is present and is notified to be ready to accompany officers into the school when possible.
|12:41 p.m.||Additional SWAT from Jefferson County arrive at the command post on Pierce Street. This team of 10 is commanded by Sgt. Barry Williams.
Reports being relayed to the command post include possible multiple shooters, a hostage situation, and gunfire and explosions in nearly every wing of the school building.
Students on cell phones inside the school are calling out — to 911, their parents and several times to local television stations.
Students calling from their cell phones report hearing shots inside the school and give numerous locations for the gunshots, including the gymnasium, the auditorium, the business wing, the music rooms, the science area and the business offices.
The news media announces that students who have safely escaped the school should call the Jefferson County Sheriff's Office or 911 to report their safety. The phones at the Sheriff's Office are immediately jammed until personnel contact local TV stations to correct the message. Students are encouraged to call the school district's parent hotline instead.
|12:43 p.m.||Deputy Simmons, leader of the first SWAT team that entered the 250,000-square-foot school, requests additional SWAT for the east side. Due to the size of the school, the numerous rooms and hallways that have to be searched, and the amount of students and faculty being rescued, Simmons calls for more assistance.|
|12:44 p.m.||Makai Hall is transported to Littleton Hospital. He is later transported to St. Anthony's Hospital by Air Life.
Dispatch reports cover fire by Denver Police Department, most likely during SWAT's rescue of Richard Castaldo at the school's upper west entrance.
Dispatch reports that an EMT dispatcher is on the phone with a party inside the school. The individual is with a critically injured victim.
|Two SWAT deputies are positioned on rooftops of houses on West Polk Avenue, the first neighborhood street just south of the school. From their vantage point, the marksmen have a clear view of the south parking lot, the library windows and the cafeteria area.
Williams' SWAT team utilizes a front-end loader parked near the command post to move around the school to the west side.
Using the front-end loader as cover, Williams' team first moves into position on the northwest corner of the school, opposite from where Simmons' SWAT team had entered the building.
Williams is advised that students have been shot and numerous bombs have exploded. The number of suspects, still in the building, is unknown but reports indicate as many as eight.
Williams' team is also told that activity has been reported in both the cafeteria and the library.
A "live" bomb blocks the outside west doors leading into the upper level hallway and entrance to the library. The closest point of entry is into the cafeteria directly underneath the library.
A window into the teachers' lounge next to the cafeteria will provide an entry point for Williams' team.
Nicole Nowlen is transported to Lutheran Medical Center.
|12:51 p.m.||Media reports that several area schools are in "lock down." Schools are locked from the inside and, for safety reasons, "no one goes out and no one goes in."|
|12:57 p.m.||Austin Eubanks and Jennifer Doyle are transported to Littleton Hospital.|
|1:00 p.m.||The Jefferson County Critical Incident (Shoot) Team is activated.|
|1:03 p.m.||Nick Foss is transported to Littleton Hospital.|
|1:04 p.m.||Richard Castaldo, rescued by SWAT from the outside upper west entrance, is transported to Swedish Medical Center.|
|1:09 p.m.||Williams' team breaks an outside window to gain entrance into the teachers' lounge. The team is met with the deafening noise of fire alarms, the flash of strobe lights, ceiling tiles hanging at odd angles and three inches of water coming in under the closed door to the cafeteria. The alarms and the sprinkler system have been set off by the explosions and the cafeteria area and adjacent rooms are flooding. Another concern is "a hissing sound and the sound of something spraying." Williams fears it might be a broken natural gas line.
Williams' team first clears the kitchen and back storage areas, evacuating groups of students and staff hiding behind locked doors.
Air Life transports Mark Kintgen from the Yukon/Caley triage to Denver Health Medical.
|1:10 p.m.||Investigators are at or en route to area hospitals as injured victims are being transported.|
|1:11 p.m.||Brian Anderson is transported to Lutheran Medical Center.|
|1:15 p.m.||Investigators arrive at the Harris and the Klebold residences.|
|1:18 p.m.||Simmons' SWAT team evacuates 30 students and faculty from south classrooms on the upper level.|
|1:22 p.m.||SWAT teams continue a search and rescue inside the school building. Simmons' team works east to west on the upper level, and Williams' team works west to east on the lower level.
Dispatch reports that Arapahoe SWAT team is on scene and ready to assist when needed.
|1:26 p.m.||Williams' team evacuates numerous students and staff from the back storage rooms and kitchen area. The students are evacuated out the same window that provided entry for the SWAT team.|
|1:32 p.m.||The cafeteria videotape shows Williams' SWAT team entering the main cafeteria area, commonly referred to as the "commons." The team had just finished clearing and evacuating students and staff from the teachers' lounge, kitchen area and back storage areas.
Williams is advised by radio that there are possible bombs throughout the school. He is told the bombs may be hidden in backpacks and constructed with timers and motion-activated devices. The information is relayed from bomb technicians who have inspected the diversionary bombs placed on Wadsworth and realize similar devices may have been placed inside the high school.
Williams' team is advised that the suspects' last known location was downstairs by the business classrooms. This information was relayed by a student on a cell phone inside the school.
|1:40 p.m.||Air Life transports Makai Hall from Littleton Hospital to St. Anthony's Hospital.|
|1:44 p.m.||Three male subjects, appearing in a field north of the high school in Clement Park, are contacted by Jefferson County Sheriff's deputies and detained for questioning.
The three are dressed in black clothing, which matches the known description of the shooters, and are spotted in an unsecured area close to the school.
These individuals, who are not Columbine students, identify themselves as the "Splatter Punks" and insist they have shown up at Columbine High School mainly out of curiosity.
The images of the three being taken into custody by law enforcement authorities, aired live on local television channels, raised numerous questions from the community about their involvement in the crime.
After initial questioning, the three youths are released the same afternoon and are re-interviewed at length on April 24. It is determined that they had no known affiliation with the Trench Coat Mafia, and, shortly thereafter, are cleared of any involvement.
|1:45 p.m.||Jefferson County SORT arrives at Leawood Elementary School where they provide perimeter security, assist with the evacuation of the elementary children to their parents, assist in the reuniting of Columbine students and parents, handle traffic control and maintain a media area outside the school building.|
|1:57 p.m.||Williams' SWAT team announces that it has found several students and faculty hiding in the ceiling of the kitchen. Six individuals are evacuated out the west side.
Dispatch tells Williams there is a male upstairs "in the library past the stairs" doing CPR on an injured party. The SWAT team is also told that a blue and white shirt is hanging on the door knob.
|1:59 p.m.||Williams asks for better directions on how to get to the injured party.|
|2:08 p.m.||Students are evacuated from the Technology Lab on the main floor.|
|2:12 p.m.||The Lakewood SWAT team, with an armored vehicle, approaches the west side of the school next to the south parking lot.|
|2:15 p.m.||SWAT positioned on the roof of a residence to the south of the school reports a sign in a window on the upper level. The sign reads, "1 bleeding to death."|
|2:17 p.m.||Williams splits his team and half clears the computer and business classrooms on the lower level southeast of the cafeteria. They evacuate two people found in the furthest business classroom out the south side.|
|2:19 p.m.||A Columbine parent, waiting at Leawood Elementary for word about his son, is transported to Littleton Hospital because of chest pains. He is one of many parents in anguish awaiting word of their children.|
|2:24 p.m.||Adam Kyler is transported to Littleton Hospital.
The second half of Williams' SWAT team, having cleared the two-story auditorium, is entering into the school's music area on the second floor where there are reports of students hiding in a music room closet. The team discovers 60 students and evacuates them in groups of 10 through a protective wall of SWAT officers and out the west side.
The same SWAT team then moves into an area across the hallway and to the left of the music room where an additional 60 students are found and safely evacuated from the building.
|2:26 p.m.||Sgt. Domenico, surveying the area from Channel 7 news helicopter, reports that someone is trying to climb out a second story window on the southwest side of the school.|
|2:28 p.m.||Simmons advises that the administration area on the upper level is cleared and his group is moving to the art and consumer education areas.|
|2:29 p.m.||The Jefferson County Sheriff's Office requests Littleton Fire to dispatch engines and rescue units to Eric Harris' residence. Already on scene are the Sheridan and Lakewood Police Department investigators, ATF personnel and Arapahoe County bomb technicians preparing to investigate a gasoline smell and the report of a bomb at the residence.|
|2:30 p.m.||Having just searched the business and computer classrooms, the first half of Williams' team clears the stairs to the upper level. Once on the upper level, Williams sees Simmons' team clearing the school to the east of where he stands.|
|2:33 p.m.||President Clinton refers to the shooting at a high school in Littleton, Colorado, during a scheduled news conference to talk about the American economy. "Ladies and Gentlemen, we all know there has been a terrible shooting at a high school in Littleton, Colorado. Because the situation, as I left to come out here, apparently is ongoing, I think it would be inappropriate for me to say anything other than I hope the American people will be praying for the students, the parents and the teachers and we'll wait for events to unfold and there will be more to say."|
|2:38 p.m.||Patrick Ireland, shot in the library and slipping in and out of consciousness, has slowly made his way to the west window. Sgt. Domenico, in a news helicopter, and deputies on the south and west sides of the school see a figure at the window and realize the young man is attempting to climb out the second story broken window. The only thing below him is a concrete sidewalk. The image of Patrick's rescue has come to epitomize the Columbine tragedy. Using the roof of an armored vehicle so they can reach him, several Lakewood SWAT members catch the young man as he falls out the window at 2:38 p.m.|
|2:39 p.m.||Patrick Ireland is transported to St. Anthony's Hospital.|
|2:40 p.m.||Forty students are evacuated out of the vocal room.
Littleton Fire shuts off the electricity and natural gas to the Harris' residence.
|2:42 p.m.||Williams' SWAT team requests medical assistance to the science area on the second floor, west side, for a teacher with multiple gunshot wounds. The teacher is Dave Sanders.
Williams' also announces that 60 students are to be evacuated from this same area.
|2:47 p.m.||Members of Williams' SWAT team evacuate approximately 60 people from the science area. Two SWAT members move the students and teachers first to the stairway landing, then down to the lower level and through the recently cleared cafeteria and out the west side door. Two SWAT members stay with Sanders waiting for paramedics.|
|2:52 p.m.||Simmons' SWAT team working on the upper east side of the building announces the band room and woodshop areas are clear. The team is progressing west down the hallways to clear various rooms including a gym and weight room.|
|3:12-3:17 p.m.||Fifty students are evacuated from the east upper level and are directed across the street to safety.|
|3:22-3:37 p.m.||The first team to enter the library is Williams' team of four Jefferson County SWAT members. A Denver SWAT officer holds the doorway. The four Jefferson County members spread out and work their way through sections of the library. They step over numerous bombs trying to get to each one of the children.
Among three victims laying on the floor under desks is Lisa Kreutz. She has been shot several times but she is alive. SWAT, seeing her wounds, calls for a paramedic.
In addition to the one girl who is injured, Williams' team reports that they have found 12 dead. Among the 12 are two males on the floor in the southwest part of the library who appear to have self-inflicted gunshot wounds to the head. Guns and numerous explosive devices lay on the ground beside the bodies. Williams advises the command post that the two males match the description of the suspects.
A female employee, hiding in the magazine room in a back part of the library, comes out of hiding. She is instructed to put her hand on the back of one of the SWAT officers, look only at the back of his helmet and follow him out of the library. She is quickly passed off to another officer and evacuated to the outside.
Three other employees subsequently are evacuated from the library, including teacher Patti Nielson who was hiding in a cupboard in a west room of the library.
Williams' SWAT team works its way to the back emergency door that opens to the outside upper level near the west entrance. Although several bombs are laying inside the door, the SWAT team realizes the urgent need to get a team of paramedics into the library to attend to Lisa Kreutz. Two paramedics come in with a backboard, put the wounded student on it and quickly get her out of the library. Lisa is transported to Denver Health Medical at 3:37 p.m.
After searching the library, Williams' SWAT team requests the bomb squad.
The other half of Williams' team and Simmons' SWAT team, still searching other parts of the school building, hear over the radio that William's first team has made it to the library and found one female still alive. They continue clearing classrooms on the upper levels, working their way toward the library.
|3:25 p.m.||Littleton Fire reports that live bombs and gasoline have been located at the Harris residence. Adjacent houses in the neighborhood are evacuated.|
|3:36 p.m.||SWAT command personnel meet at the east doors of the school to discuss follow up sweeps of the school and to relieve initial teams, replenishing them with fresh SWAT teams from other agencies.
Simmons' team, after clearing the gymnasium and weight room, enters a north-south hallway which is where the library is located. The team arrives outside the library as Williams' team completes clearing the library.
|3:40 p.m.||Teacher Patti Nielson is transported to Littleton Hospital.|
|3:55 p.m.||Lakewood SWAT reports two cars on the southwest side of the school are possibly booby trapped. One car is described as being a black Honda Civic, Mercedes or BMW with NIN bumper stickers. The other is a blue 1980s two-door with a Ramstein sticker.|
|4:00 p.m.||Bomb technicians remove an explosive device from the Harris residence.|
|4:04 p.m.||A Littleton fire captain enters the school and is able to silence the fire alarms and shut off the emergency sprinkler systems.|
|4:35 p.m.||Two explosions are reported on the north side of the school. SWAT advises that they are shock locks fired by a SWAT team. Shock locks are explosive devices used to gain entry into locked rooms.|
|4:38 p.m.||Dr. Christopher Colwell, attending emergency room physician at Denver Health Medical Center, and Robert Montoya, a Denver Health paramedic, are escorted by SWAT team members through the library "to look for any signs of life." Dr. Colwell had already pronounced Rachel Scott and Daniel Rohrbough, two of the youths shot outside, as deceased.|
|4:45 p.m.||Colwell performs a second sweep of the library, this time pronouncing each of the 10 victims and the two suspects deceased. He is also escorted to the science area where he pronounces teacher Dave Sanders as deceased.|