A gunman, possibly carrying explosives, has entered the headquarters of the Discovery Channel and fired shots, RadarOnline.com is reporting.
According to police in Silver Spring, Md., a report came in about 1 pm of a gunman who entered the building.
Employees inside were told to take cover in locked offices and police have sent SWAT teams to the area to seal off nearby roads.
The 911 call reported that shots had been fired, according to the Washington Post.
Local media is reporting children at a day care center in the Building have been safely evacuated to a nearby McDonalds.