Four people were killed and two others, both minors, injured when a gunman opened fire in a Philadelphia neighborhood on Monday, police said.

The injured were described as 2-year-olds and 13-year-olds, both boys, who were in stable condition at a hospital, Philadelphia Police Commissioner Danielle M. Outlaw said at a news conference.

Police believe they have the gunman in custody. Outlaw said he had not been identified.

She described him as a 40-year-old man who had a semi-automatic rifle, a pistol, a ballistic vest and a police scanner.

He also had several ammunition magazines, the commissioner said. She described the rifle as being in the style of the AR-15, a weapon initially developed for military use.

Philadelphia Police Commissioner Danielle Outlaw updates the media after Monday night's fatal shooting.
Philadelphia Police Commissioner Danielle Outlaw updates the media after Monday night’s fatal shooting.NBC10 Philadelphia

Officers responding to the attack at 8:29 p.m. heard gunshots and gave chase, and the suspect continued to fire, Outlaw said at an evening news conference.

“I was actively firing a firearm at the time,” he said.

He finally stopped when he was cornered in an alley and surrendered without incident, the commissioner said. She praised the first officers on the scene.

«I can’t even describe the level of bravery and courage that was shown,» Outlaw said.