Four people were killed and at least 10 were shot - two of the victims police officers - at the Washington, D.C. Navy Yard Monday morning by more than one gunman.
At about 10:20 a.m., one shooter had been reported contained. However, at least one other gunman remained at large.
One of those shot was a D.C. police officer, reported NBC News' Pete Williams. Another was a base security officer.
The conditions of the victims are unknown, but George Washington Hospital reported that at least one victim has been transported to that hospital.
The U.S. Navy said the shooting began at about 8:20 a.m. with three shots fired inside Building #197 at the Naval Sea Systems Command Headquarters, 1336 Isaac Hull Ave. in the Southeast section of the District. U.S. military officials say the gunman - armed with an AR-15, a military-style assault weapon - first shot the base security officer.
One victim was reported to be on the roof of a building, reported News4's Tony Tull. A U.S. Park Police helicopter hovering above the scene around 9:50 a.m. lowered a basket to a building and lifted what appeared to be a shooting victim from the roof. The helicopter came back to the scene just after 10 a.m. to retrieve another victim.
But other details were sketchy from the still-active scene. The shots continued to ring out through the morning, including a volley that Tull reported at about 9:20 a.m.
Authorities originally believed there was a lone gunman, but sources later confirmed to News4 that the shooting was carried out by at least two gunmen.
Federal and local emergency personnel converged on the scene, "and a shelter in place order has been issued for Navy Yard personnel," the Navy said. Among the responders was a federal SWAT unit.
D.C. Public Schools put six schools and one administrative building on lockdown, meaning no visitors or staff may enter or leave the building and recess for students is inside. These schools are affected:
At about 10:20 a.m., one shooter had been reported contained. However, at least one other gunman remained at large.
One of those shot was a D.C. police officer, reported NBC News' Pete Williams. Another was a base security officer.
The conditions of the victims are unknown, but George Washington Hospital reported that at least one victim has been transported to that hospital.
The U.S. Navy said the shooting began at about 8:20 a.m. with three shots fired inside Building #197 at the Naval Sea Systems Command Headquarters, 1336 Isaac Hull Ave. in the Southeast section of the District. U.S. military officials say the gunman - armed with an AR-15, a military-style assault weapon - first shot the base security officer.
One victim was reported to be on the roof of a building, reported News4's Tony Tull. A U.S. Park Police helicopter hovering above the scene around 9:50 a.m. lowered a basket to a building and lifted what appeared to be a shooting victim from the roof. The helicopter came back to the scene just after 10 a.m. to retrieve another victim.
But other details were sketchy from the still-active scene. The shots continued to ring out through the morning, including a volley that Tull reported at about 9:20 a.m.
Authorities originally believed there was a lone gunman, but sources later confirmed to News4 that the shooting was carried out by at least two gunmen.
Federal and local emergency personnel converged on the scene, "and a shelter in place order has been issued for Navy Yard personnel," the Navy said. Among the responders was a federal SWAT unit.
D.C. Public Schools put six schools and one administrative building on lockdown, meaning no visitors or staff may enter or leave the building and recess for students is inside. These schools are affected:

