Dr. Lee Silverman, a psychiatrist, was grazed in the temple during the gunfight in his office with patient Richard Plotts, according to District Attorney Jack Whelan.
Whelan identified the caseworker killed Thursday afternoon at Mercy Fitzgerald Hospital as Theresa Hunt, 53. Hunt, who was from Philadelphia, had accompanied Plotts to an appointment with Silverman at a psychiatric crisis center adjacent to the hospital in Darby, just southwest of Philadelphia, authorities said.
"When the caseworker was shot, (Silverman) crouched down behind the desk to avoid him being shot," Whelan said. "He was able to reach for his weapon, and realizing it was a life or death situation, was able to engage the defendant in the exchange of gunfire."
The motive for the shooting remained unclear late Thursday, but later, it was assumed that he might have had issues with the doctor over his treatment plan.
However, it is still unknown if that's why Silverman was armed, apparently against hospital policy.
"We do believe that there were some issues between the doctor and the patient, but whether or not he actually feared him is unclear," the prosecutor said. "From all accounts, (he) would have acted in self-defense."
Whelan said that Plotts, 49, was still in surgery Thursday evening at the Hospital of the University of Pennsylvania, while Silverman had been treated and released. Telephone calls to the doctor's home went unanswered.
The exchange of gunfire occurred on the third floor of the Wellness Center at Mercy Fitzgerald, a 204-bed community teaching hospital. Authorities said there are no surveillance cameras in the doctor's office or the waiting area outside. They also said the center had no metal detectors.
Patients waiting in the first-floor lobby reported a tense scene when police arrived and ordered everyone out. Most of the patients were elderly.
"I dozed off, and I heard the cop shouting, 'Come on, come on, get out!'" said Millicent Russell, of Lansdowne, who was waiting for a 3 p.m. appointment. "There were people with walkers and canes and stuff. All these cops were outside running here and there with these guns."