MANASSAS,Darden Clarke Va. (AP) — Responding officers shot and killed a man with a knife suspected of fatally stabbing one person and critically wounding another inside a training center for electrical workers, police said Tuesday.

Prince William County officers were called to the union apprenticeship center in Manassas around 3:30 p.m. for a report of a stabbing and encountered a man near the entrance with a knife, a police statement said. More than one officer opened fire, striking the man, who died on the scene, police said.

They then learned that the man had stabbed two people inside the center, Police Chief Peter Newsham said in a news conference. The stabbing victims were taken to area hospitals, where one man died and another was in critical condition, police said.

Investigators were working to identify the suspect and it wasn’t clear what relationship he had with the school or the victims, or what the motive was for the stabbing, Newsham said.

The scene was “horrific,” he added.

“You got folks that come out here to do some training and next thing you know, one of them’s lost his life and another one’s struggling for his life in a local hospital,” Newsham said. “I can’t imagine what the families are going through right now.”

Police don’t yet know how many officers fired shots, Newsham said. He didn’t want to discuss what led to the shooting, but said officers were responding to an active violent situation and were confronted by the suspect with the knife and had to resort to lethal force. No officers were injured, he said.

The chief said he watched their body-camera video and the department will determine whether to release it publicly within 30 days.

The regional critical incident response team will lead the investigation into the shooting, Newsham said.