Police in Maryland say a gunman is inside Discovery Communications headquarters.

Police: Gunman inside Discovery TV building in Md.

WASHINGTON — Police in Maryland say a gunman is inside the Discovery Channel building in the Washington suburbs.

Footage from WJLA-TV showed police SUVs and cruisers with their lights on outside the office building in Silver Spring.

Montgomery County police Cpl. Dan Friz told the channel that a gunman was in the building.

Police did not immediately return calls from The Associated Press.