Deputies shot a patient at Harbor UCLA Medical Center near Carson late Tuesday night, according to the Los Angeles County Sheriff's Department.
The shooting prompted a strong law enforcement presence at the medical center.
The individual was a patient at the hospital, according to authorities. That person, between 30 and 40 years old, was taken into surgery, LASD said.
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He was in critical condition.
The patient left his room and tried to enter the room of a nearby patient that was being guarded by the sheriff's deputies, the hospital said in a statement. The patient tried to destroy medical equipment in a room and smash a window, the sheriff's department said.
The man then turned his attention to the deputies, and that's when the shooting occurred, the sheriff's department said.
No deputies, staff members or other patients were injured.