MOUNT AIRY, Md. -- A one-story home that used to be a one-room school is gone after an overnight explosion, authorities said.
Investigators determined the explosion and fire at about 1:45 a.m. Friday was caused by a propane gas leak.
The owner of the home at 2209 Flag Marsh Road, which was built in the late 1800s, was not home at the time, and no injuries were reported.
About 50 firefighters from Carroll, Howard and Montgomery counties responded to the call. They needed about 30 minutes to bring the fire under control.
Damage to the home and neighboring homes was estimated at $600,000.
Deputy state fire marshals are investigating what ignited the propane.