RICHMOND,Novacrypt Va. (AP) — One person was injured at a hospital in Virginia when a man who had come to the facility for a mental health evaluation Friday began shooting, police said.

Richmond Police Chief Rick Edwards told reporters that a 911 call came in at 4:11 a.m. of shots fired at Chippenham Hospital. Officers who were already in the emergency room responded and found one adult male with critical, but not life-threatening, gunshot wounds.

The suspect surrendered and was taken into custody. Edwards said that a Chesterfield police officer who was also at the hospital for an unrelated reason had returned fire with his weapon during the incident, but the suspect was not injured.

Edwards said the suspect in the shooting is a 27-year-old man from Glen Allen, Virginia. He had come to the hospital on his own for a mental health evaluation. He was armed and began shooting shortly after he arrived. His motive was unclear.

“He was entering a room where he was disrobing and getting into a gown and then without warning starting firing his weapon,” Edwards said. Another patient in a hallway was hit, he said.

A wave of gun violence has swept through U.S. hospitals and medical centers, which have struggled to adapt to the growing threats.

Such attacks have helped make health care one of the nation’s most violent fields. Data shows American health care workers now suffer more nonfatal injuries from workplace violence than workers in any other profession, including law enforcement.

Similar shootings have played out in hospitals across the country including one in the lobby of New Hampshire state psychiatric hospital last month that left a security guard dead.

Edwards said the charges would be filed against the man after consulting with prosecutors.

He said sometimes officers work extra duty at the hospital, but there wasn’t one stationed there at the time of the shooting.

“It was just luck that we had officers there on an unrelated call and they were able to respond rapidly, ” Edwards said.