A 42-year-old man was shot and killed by a courthouse security officer Thursday morning after allegedly attempting to discharge a firearm at a federal courthouse in Nashville, Tennessee, before switching to a knife, according to authorities. The incident occurred shortly before 9:30 a.m. at the courthouse in the 700 block of Church Street.

The Tennessee Bureau of Investigation identified the man as Jack Henson II, who was from out of state, according to the Metropolitan Nashville Police Department.

Don Aaron, the department’s public affairs director, said the man entered through the courthouse’s front door and approached the security checkpoint carrying a pistol. Investigators believe he attempted to fire the weapon, but it did not discharge.

“We believe that the individual attempted to discharge the gun, but it did not fire,” Aaron said during a briefing.

Authorities said the encounter escalated when Henson switched to a knife and confronted an officer staffing the checkpoint. The officer opened fire, critically injuring him.

Henson was transported to Vanderbilt University Medical Center, where he was pronounced dead. No officers were injured during the incident.

First Assistant U.S. Attorney Robert McGuire confirmed that the officer involved was a member of the courthouse security team working with the U.S. Marshals Service, the federal agency responsible for protecting federal judicial facilities and personnel.

Following the shooting, police searched the vehicle Henson had used to reach the courthouse. The car, which had North Carolina license plates, was parked on Seventh Avenue. Officers and a police dog team examined the vehicle but found nothing threatening inside, Aaron said.

The Tennessee Bureau of Investigation is leading the investigation at the request of District Attorney General Glenn Funk and the U.S. Marshals Service. Agents are collecting evidence and interviewing witnesses to establish the sequence of events that led to the deadly encounter.

Authorities have not released further details about a possible motive. The investigation remains ongoing as officials work to determine precisely what happened at the courthouse security checkpoint.