Maryland Shopping Center Explosion Ruled Accidental

Maryland fire investigators have ruled that a recent gas explosion at a strip mall was accidental.

Officials say Thursday’s explosion at the Penn Mar shopping center in Forestville was due to a buildup of natural gas. They say insurance investigators from the center’s management company are going to try to identify the cause of the gas release.

Officials from the county fire department also will review the incident with the National Institute for Occupational Safety and Health. The federal agency makes recommendations on how to prevent work-related injuries and illness.

Nine people, including eight firefighters, were injured in the blast and taken to area hospitals. Authorities say all of them have been released.