Police were called to Thomas Jefferson University Hospital just after midnight in response to a report of a shooter on the ninth floor, Philadelphia Police Commissioner Danielle Outlaw said.
When officers responded, Outlaw said, they learned the certified nursing assistant (CNA) had been shot by another hospital employee, who left the hospital in a U-Haul van.
About an hour later, someone near 40th Street and Parkside Avenue flagged down nearby police and said a man wearing scrubs was firing a weapon, Outlaw said.
When additional officers arrived, the suspect began shooting at them, and all four officers fired back, the police commissioner said.
Two officers were shot; one is in critical but stable condition, and the other is in stable condition, Outlaw said.
The 55-year-old suspect was also shot and is in critical condition, the police chief said.
The motive for the hospital shooting has not been determined.