[Washington Police Chief Cathy] Lanier initially said authorities were looking for two other potential shooters dressed in military style clothing. But shortly after she announced a detailed description of two suspects, city officials said one had been located and cleared.NBC's Pete Williams identifies the dead shooter as 34 year-old Aaron Alexis of Fort Worth, Texas. According to Williams, Alexis was a contractor at the facility. More on Alexis from the New York Times:
Senior law enforcement officials identified the gunman as Aaron Alexis, 34. A senior law enforcement official said the authorities had identified the dead gunman through his fingerprints.With the situation still unsettled, the Washington Nationals postponed tonight's game against the Atlanta Braves. Meanwhile, the U.S. Senate is blocking people from leaving or entering the building until 5:00 PM ET.
Three weapons were found on the gunman: an AR-15 assault rifle, a shotgun and a semiautomatic pistol, the official said.
[Alexis] is believed to have a criminal record there and to be a holder of a concealed carry weapon permit.
That official says Alexis is believed to have gotten into the Navy Yard by using someone else's identification card. It is not yet clear if that individual was an accomplice or if that person's ID card was stolen.
1:16 PM PT: Here's Aaron Alexis's arrest report for discharging his weapon inside his apartment. From the report: "He said that he was trying to clean his gun while cooking and that his hands were slippery."
1:21 PM PT: D.C. Mayor Vincent Gray says the death toll is now 13, including the shooter. I'm updating the headline of this post accordingly.