The FBI has identified the alleged gunman who opened fire at the Washington Navy Yard on Monday as Aaron Alexis, a 34-year-old former Army reservist who was born in Queens, N.Y. Federal officials released photos of the suspect Monday evening, asking the public with any information about him to contact the FBI's D.C. field office at (202) 278-2000 or 1-800-CALL-FBI. Media outlets, meanwhile, have been scrambling to put together their own sketch of the man who allegedly killed at least 13 and injured a dozen others before being killed reportedly while exchanging gunfire with police.

Below is a sampling of the details that began to emerge Monday evening. Given this continues to be a developing situation, it's important to treat the unconfirmed details about Alexis with a healthy degree of skepticism, and to pay attention to the sourcing, some of which is obviously much stronger than others.

Alexis Spent Nearly Four Years as a Navy Reservist (source: Military records, via New York Times):

According to the Navy, Mr. Alexis enlisted as a full-time reservist in May 2007 and left the service in January 2011. He served as an aviation electrician, and the highest rank he achieved was mate third class. From February 2008 to January 2011, he was assigned to Fleet Logistics Support Squadron 46, in Fort Worth. The Navy said Mr. Alexis had been awarded the National Defense Service Medal and the Global War on Terrorism Service Medal.

Alexis Was a Defense Contractor at Some Point (source: Navy Secretary Ray Mabus, via CNN):

When asked whether Alexis was authorized to be at the Navy Yard, Secretary of the Navy Ray Mabus said that was "part of the investigation." … "The only thing we know was that at one point, he was a Navy contractor. Whether he was today, I don’t know,” Mabus told CNN's Wolf Blitzer.