MARYCLAIRE DALE
Associated Press

PHILADELPHIA (AP) — Authorities found two more guns at the home of a man suspected of fatally shooting his caseworker and grazing his psychiatrist in suburban Philadelphia before the doctor pulled out his own weapon and fired back.

The weapons and a computer were seized from Richard Plotts’ home in Clifton Heights, Delaware County District Attorney Jack Whelan said Saturday.

Authorities plan to arraign Plotts on a murder charge after he awakens at the Hospital of the University of Pennsylvania, where he underwent surgery late Thursday. He is sedated and under guard.

Plotts, 49, was at Mercy Fitzgerald Hospital for an appointment earlier Thursday when he began ranting about its gun ban and then drew a gun from his waistband and shot his caseworker, 53-year-old Theresa Hunt, psychiatrist Lee Silverman told police.

Silverman crouched behind a chair, pulled out his own weapon and fired back, striking Plotts several times, authorities said.

Plotts had 39 unspent bullets on him when he was wrestled to the ground, police said. Two guns were also found at the scene, including a revolver that police say Plotts used to kill Hunt.

“If the doctor did not have a firearm, (and) the doctor did not utilize the firearm, he’d be dead today, and I believe that other people in that facility would also be dead,” Whelan said.

Police in Upper Darby, where Plotts once lived, were aware of at least three mental health commitments, including once after he cut his wrists and once when he threatened suicide. Whelan said Plotts had spent time in a mental health facility, but he did not discuss any potential diagnosis.

Plotts’s record also includes past assault, drug and gun charges, including one of possessing a weapon when banned from doing so, according to police and court records. And he has been barred from at least one residential shelter because of his violent history, Upper Darby police Superintendent Michael Chitwood said.

“The caseworkers and the doctors and the catchment centers — they know who violent individuals are because they’re frequent fliers,” Chitwood said. “And the system is not geared toward keeping these people housed somewhere until they start to be better.”

Plotts was expected to be charged with first-degree murder in Hunt’s death, along with other charges in the shots fired at Silverman, who was struck in the thumb and grazed in the temple.

The psychiatrist has not spoken publicly about the encounter with his patient. His wife said Friday he was resting at home and did not want to comment.

Cathy Nickel, a neighbor of Plotts when he lived at an apartment complex in Upper Darby, saw a caseworker move him out of the building about a year ago. As he was taken away, she said, he yelled, “You haven’t heard the end of me!”

Plotts doesn’t have a listed home number, and it was unclear if he has relatives in the area.

Hospital policy bars anyone except on-duty law enforcement officers from carrying weapons on campus, said a Mercy Health System spokeswoman. Nonetheless, the hospital thanked Silverman and colleagues who helped subdue Plotts for their “brave and difficult action” and said it would welcome Silverman back.

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