A Louisiana man shot and killed his doctor at a hospital before walking outside and turning the gun on himself, authorities said Thursday.

The Jefferson Parish Sheriff’s Office identified the gunman as John P. Thomas, 73, in the murder-suicide. Police confirmed that Thomas was one of Dr. Elbert Goodier’s patients at East Jefferson General Hospital, WVUE-TV reported.

Thomas didn’t have a criminal past. But family members told police he suffered from a mental illness, according to the Fox affiliate.

“(Dr. Goodier was) a very nice guy," Jefferson Parish County Coroner Dr. Gerry Cvitanovich told WVUE-TV. "If you called him late at night, he was always prepared to help assist and take care of his patients."

Cvitanovich said he was with his mom at the hospital for a doctor’s appointment when someone came rushing in and said a doctor had been shot and killed.

Authorities said Thomas walked into Goodier’s office at the Metairie hospital and then killed the doctor while he was meeting with a patient at around 2:20 p.m.. Thomas then fled the scene and entered a nearby Wendy’s, saw a sheriff’s deputy and put the gun in his mouth and fired, police said.

"I think it's awful because we have very few murders in Metairie, and I personally come to that office, that building, many times over the last 10 years or better, and never hear anything like this. It's very, very depressing," Richard Wise, a neighbor, told WVUE-TV.

East Jefferson General Hospital President Dr. Mark J. Peters called Goodier’s death a “tragic loss.”

“Dr. Goodier was respected and beloved by all who had the privilege of knowing him. Our hearts and sympathies go out to his family, his friends, his staff and all who knew him,” Peters said in a statement. “Our chaplains are available should anyone wish to speak with them. We will be sending out more information as arrangements are made.”

According to the New Orleans Times-Picayune, Goodier, 75, was a board-certified urologist who had practiced medicine for 50 years around the New Orleans area. He was a graduate of the LSU School of Medicine, completed an internship at Charity Hospital and his residency at Ochsner Medical Center.

He is survived by his wife Catherine, his son Michael, and his two daughters Christine Ross and Gina Goodier, the hospital said.

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