Twelve people have been killed and several more wounded in a shooting at the US Navy Yard in Washington, DC. One shooter has also been killed, with officials saying two more potentially could be at large.
Washington Chief of Police Cathy Lanier said Monday that 13 people including the shooter were killed in the attack. The Federal Bureau of Investigation (FBI) named the suspected shooter as former serviceman Aaron Alexis, 34 (pictured below in combination photo).
Lanier had earlier confirmed in a press conference that police were "actively engaged" in a search for two other potential shooters.
"We have one shooter that we believe was involved in this that is deceased," Lanier said. "The big concern for us right now is that we potentially have two other shooters that we have not been located at this point."
The suspects were reportedly wearing military-style clothing.
The Washington Hospital Center said that three people - two women and a male police officer - were being treated for gunshot wounds. All were in critical condition, but chief medical officer Janis Orlowski said "their chances for survival are very good."
The attack occurred around 8:20 a.m. (12:20 UTC) at the headquarters Naval Sea Systems Command, which buys, builds, and maintains submarines and ships, as well as develops combat systems.
Some witnesses described a gunman opening fire from a third-floor balcony down onto a cafeteria, while others saw a gunman shoot down a third-floor hallway.
Hundreds of police and federal agents from multiple law enforcement agencies responded to the scene. Departures from the city's Reagan National Airport were halted for around 90 minutes due to the shooting, while area schools were locked down.
Washington Mayor Vincent Gray described the attack as an "isolated incident" and Lanier said that there were "no indications of motive at this time."
President Barack Obama called the attack a tragedy, and vowed to make sure "whoever carried out this cowardly act is held responsible."
The Naval Sea Systems Command is part of the Navy Yard complex, the oldest military installation in the US.
The complex, which is located approximately a mile (1.6 kilometers) south of the US Capitol building, also houses a residence for the chief of the US Navy.
dr/rc (AP, AFP, dpa, Reuters)