Authorities Probe Arson at Maryland High School

Montgomery County fire officials say someone threw an incendiary device into a classroom at Walt Whitman High School, located in Bethesda, causing a small explosion and fire.

Assistant Chief Scott Graham of the Montgomery County Fire Department says officials aren’t sure what kind of device started the fire in the classroom around the back of the building before midnight Friday. Authorities are reviewing recordings from security cameras around the school for clues about who started the fire.

The fire set off the sprinkler system, which caused water damage in several classrooms on the first and second floors. Crews worked through the weekend to clean up the damage and classes are expected to start on time on Monday.