A worker returned to an Alaska hospital a day after being fired and staged a shooting spree that left one of his ex-supervisors dead and another critically injured before he was fatally shot in a standoff with authorities.

Mike Webb, 55, died about two hours after Joseph Marchetti fired multiple shots just before 10 a.m. inside Central Peninsula Hospital in Soldotna. The shooting sent people scattering, spokeswoman Bonnie Nichols said.

"People were running for their lives," she said.

Nichols said Marchetti also was shooting randomly through the main corridor before he left the hospital. The hospital's chief financial officer, Jason Paret, heard the first shot and went around a corner to see what was going on, encountering the gunman, Nichols said.

"Marchetti started running after him, but he managed to get away," she said. "As he ran, he was yelling at co-workers that a gunman was on the loose."

Marchetti had worked in the hospital's imaging department until he was fired Tuesday, Nichols said.

Marchetti moved to Alaska a year ago. He previously worked at Nebraska Medical Center in Omaha, according to Nichols.

Troopers said the assailant had a rifle and a handgun. Afterward, troopers set up a perimeter outside the hospital to contain the suspect, who was ultimately shot by troopers, spokeswoman Megan Peters said. Marchetti was shot in the hospital's north parking lot in a standoff with authorities, according to Nichols.

Three troopers fired their weapons, Peters said. Under department policy, the officers will be placed on administrative leave for three days. Their names will be released Saturday.

Nichols identified the other shooting victim as 57-year-old Margaret Stroup.

Stroup was shot multiple times in the chest and underwent surgery. Nichols said Stroup was listed in critical and would be flown Wednesday night to a hospital in Anchorage, 75 miles to the northeast.

Nichols said the victims are the former supervisors of Marchetti, who worked in the imaging department. Webb was the hospital's information services director and Stroup is the imaging services director.

Nichols called Webb "a very kind man" who was well respected and admired by hospital staffers.

Nichols said she didn't know why Marchetti's employment was terminated.

The shooting, Nichols said, "obviously had something to do with him losing his job."

Local schools were briefly placed in lockdown after the shooting.

In Omaha, Marchetti worked at the medical center from October 2001 to October 2007.

Nebraska Medical Center spokeswoman Andrea McMaster said Marchetti decided to leave the job on his own in 2007 because he was moving.

McMaster said Marchetti did information technology work at the hospital. He helped maintain databases for the hospital's cardiac service line.

No other details about Marchetti's work at the Nebraska Medical Center were immediately available, McMaster said.