The footage is a "portion" of the events that happened at Henry Pratt Co. — one of the largest makers of industrial water valves — when Gary Martin, a 45-year-old disgruntled employee, opened fire.
The clip showed four camera angles that included police pulling up to the warehouse, and Martin after the shooting. After police arrived on scene and ran to the building, he appeared to pace the lobby, often looking through the front doors throughout the nearly 10-minute-long video.
A few minutes in, Martin could be seen shooting at the police officers through the front door. Soon after, an armored police truck was seen ramming the lobby doors, before seven armed officers slowly entered the building.
The footage ended there. Martin, a 15-year-old employee of the company, was killed at the scene. He was shot six times, one of which was likely self-inflicted, the Chicago Tribune reported, citing autopsy results.
The Aurora Police Department wrote on Facebook, alongside the video, that Martin had one pistol and eight pistol magazines on him, and he fired 64 rounds during the incident.
Police said they "were not careless" in releasing the surveillance footage, and chose to do so to be transparent with the community.
"We agree that you have a right to see for yourself what transpired at the Henry Pratt facility that day where, sadly, five members of our community lost their lives, and five of our police officers were shot while simply doing their jobs," police wrote.
Clayton Parks, 32, Vicente Juarez, 54, Josh Pinkard, 37, and Russell Beyer, 47, were killed in the shooting. Trevor Wehner, a 21-year-old intern at his first day on the job, was also killed.
Fox News' Louis Casiano and The Associated Press contributed to this report.