A 55-year-old man shot and killed a coworker inside Jefferson University Hospital in Philadelphia before taking off in a U-Haul early Monday. He later shot and wounded two officers before being wounded himself by police returning fire, authorities say.

Philadelphia Police Commissioner Danielle Outlaw said the victim was a 43-year-old certified nursing assistant. He was pronounced dead a short time after being shot inside Jefferson Hospital, ABC6 reports.

The commissioner said it is not clear if the suspect was working at the time, but entered the hospital wearing scrubs. He possibly accessed areas that only employees can enter, Outlaw said.

Outlaw said around 1:25 a.m., approximately an hour after the shooting, 16th district officers were flagged down.

"The report was that there was a male in scrubs, with a weapon or a long gun, who was potentially firing rounds in the air or just had a gun," Outlaw said.

According to the commissioner, arriving officers encountered the male suspect who then began shooting at them. Four of the officers returned fire. Two officers were wounded.

A 30-year-old officer was hit in the right elbow. He is in critical but stable condition at Penn Presbyterian Medical Center. The officer will undergo surgery and is expected to survive.

A 32-year-old officer was struck in the nose and was treated and released from Penn Presbyterian.

The suspect was struck in the upper body and neck, Outlaw said.

"We learned that he was wearing body armor, and was carrying multiple weapons. In addition to the long gun which was believed to be an AR-15, he was also carrying some form of a semi-automatic handgun," Outlaw said. An AR-variant rifle was recovered at the scene.