BALTIMORE — Baltimore police officers responding to the sound of gunshots near an apartment building fatally shot a man who fired at them with an AR-15-style rifle, authorities said today.

No officers or anyone else was wounded in the shooting Thursday night in a neighborhood on the city’s west side, police spokesman T.J. Smith said. He added that it wasn’t immediately clear why the man had started shooting.

Four plainclothes officers riding in an unmarked car with the windows down heard gunfire coming from the building about 9:30 p.m. Thursday, Smith said. The officers drove toward the sound and saw a man shooting an AR-15-style weapon, according to Smith, who said the man started firing toward the officers, and two returned fire.

The suspect was shot at least once and retreated to the apartment building, according to the spokesman.

Officers surrounded the building and searched the area. Smith said authorities found the gun in a tree line behind the apartment complex and the suspect inside on the second level with at least one bullet wound to his upper body. The man was taken to a hospital, where he was pronounced dead, Smith said.