An ex-employee of a real estate company shot his former boss in the head Thursday afternoon in Los Angeles, according to police.

The victim, who has not been named, was in a critical condition in a hospital Thursday.

The shooting happened at Venture Commercial Realty on the fourth floor of a high-rise building in Koreatown.

Fire officials received a report of shots fired at about 3:45 p.m. local time (6:45 p.m. ET).

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LAPD Sgt. Dino Caldera said that officers had gone room-to-room in the building, searching for the gunman.

"Officers responded … to what they believed at that time was an active shooter-site type of situation," he said. "So they used those kind of tactics to go into the building and clear the rooms as they entered."

The suspect put his hands up when confronted by police and was arrested. He was expected to be booked on a charge of attempted murder.