Four killed, 2 injured in Pennsylvania house explosion

Four people were dead and two others were injured after a house exploded in Pennsylvania on Thursday night, officials said.

Two additional people may be unaccounted for, according to Pottstown Borough Manager Justin Keller.

The explosion happened around 8 p.m. in the borough, about 30 miles northwest of Philadelphia. The cause of the explosion was not known.

The federal Bureau of Alcohol, Tobacco, Firearms and Explosives and the state fire marshal s office were among the agencies responding to the scene, Keller told reporters.

Todd Stieritz, a spokesman for the Montgomery County Department of Public Safety, said the first 911 calls about the explosion came in at 8: 07 p.m.

The identities and ages of the four killed were not released by officials.

The two wounded people were taken to area hospitals, Keller said. Their conditions were not released.

Another briefing was planned for Friday.

Photos of the scene from NBC Philadelphia showed debris littering the street.

Russell Noll, who lives nearby, told the station that I heard a huge explosion and I thought a bomb went off. Another woman told the station that the blast blew out her windows.