SMITHSBURG, Md. — Questions remained Friday about the motive of a gunman who killed three people and injured two others in a shooting Thursday at a manufacturing facility near Smithsburg. 

The gunman, a worker at the factory who was also injured, was in custody and charges were expected, said Washington County Sheriff Doug Mullendore. His identity was not released, but authorities were expected to release more information on Friday.

A Maryland State Police trooper was also injured after he exchanged gunfire with the suspect, Mullendore said Thursday. The state trooper’s injuries were not life-threatening and he was released from the hospital late Thursday, the Washington County Sheriff’s Office wrote in a Facebook post late Thursday.

The shooting happened Thursday afternoon at Columbia Machine, a factory in Smithsburg, about 75 miles northwest of Baltimore near the Pennsylvania border. Deputies arrived around 2:30 p.m., and found four employees had been shot, three of them fatally. 

WORKPLACE SHOOTING:At least 3 dead, 3 injured in mass shooting at Maryland manufacturing facility

Here’s what we know.

Who was the gunman?

The suspected shooter is a 23-year-old man who lives in West Virginia and was employed at the factory, Mullendore said. A semi-automatic handgun was used in the shooting, but authorities haven’t detailed the caliber, make or model.

The suspect fled the factory before deputies arrived, but a state trooper encountered him and they exchanged shots, Mullendore said. 

The Washington County Sheriff’s Office was investigating the motive of the suspect, who was in custody at Meritus Medical Center as of Friday morning. Charges were expected, authorities said.

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