At least four people have been killed and eight people have been injured by a suspected lone gunman located at the Washington Navy Yard Monday morning, according to local news reports and confirmed by the U.S. Navy.
The suspected shooter, described as a black male, was likely armed with an AR-15, a military-style assault weapon, and has also reportedly been injured.
Ronald Reagan Washington National Airport has also temporarily has suspended flights because of the proximity of SWAT and rescue helicopters over the Navy Yard.
About 3,000 people – civilian and military – work at the Naval Sea Systems command headquarters where the shooting took place and have been asked to "shelter in place" following the initial reports of the shooting at about 8:30 a.m.
Among the injured are two law enforcement officers, one federal and one local, according to The Washington Post.
Police, fire and rescue vehicles have swamped the scene, where the gunman is still at large and SWAT teams have been seen entering the building.
There were reports of a second round of gunshots at around 9:15 a.m., according to NBC News.
Area schools in the densely populated neighborhood have been locked down as a precautionary measure.