The dead gunman in Monday's shooting at the Washington Navy Yard is 34-year-old Aaron Alexis, a Navy veteran and native of Brooklyn, according to an FBI official.
Police say it is unclear if Alexis acted alone. Authorities are still searching for another possible suspect: a black man in his 40s with gray sideburns, wearing an olive-drab military-style uniform.
The Washington Post reports that military personnel records show that Alexis spent nearly four years in the Navy as a full-time reservist from May 2007 until he was discharged in January 2011.
It's not clear if he was employed as a civilian employee at the Navy Yard and how he obtained the ID card of a Stafford man who is a retired Navy petty officer. Federal investigators were at the man's home for several hours today.
Mayor Vincent Gray says that 13 people including Alexis were killed in the rampage that started at 8:20 this morning.