Ronald Gilbert was shot and killed on Monday in his Orange County medical office.

Police were called to scene, where they arrested “an elderly man” who was found in an examination room with the doctor, whom he had allegedly killed.

According to authorities, police responded to several 911 calls, in which witnesses reported six or seven gun shots at the medical office near Hoag Hospital in Orange County, Newport Beach police spokeswoman Kathy Lowe, told the Los Angeles Times. After arriving on the scene, officers reportedly found one man dead from gunshot wounds in a patient examination room, Lowe said.

Witnesses told several media outlets that the doctor was a urologist. The AP reported that the floor where the shooting occurred included the offices for a Orange Coast Urology, which lists three doctors on its staff.

Becky Calderwood, who works two doors down from the office, told the Los Angeles Times that the gunman was a patient.

"I sit right at the front desk, I would have caught the first bullet," Calderwood told the L.A. Times.

Police believe that the shooter specifically targeted Gilbert, given that he passed through a major portion of the building and waited until he was in an office to fire the shots.

"It does appear to be an isolated incident," Deputy Chief David McGill told the  newspaper.

Another report indicated that Gilbert was supposed to perform surgery on the patient.

The suspect is reportedly still in custody as officials attempt to find a motive for the shooting.

Gilbert was a member of the orthodox Jewish community in Newport Beach, and they have been rattled by his death.

"He was one of the most caring, giving, generous people I knew," childhood friend, Gerry Crews, told the Jewish Press. "I doubt you would find anyone who would say anything bad about him."

Gilbert is survived by his wife and two children.