13th Death in Navy Yard shooting
Authorities still looking for a second person
The D.C. mayor says 13 people have died in the shooting rampage, including the gunman.
Mayor Vincent Gray said at a news conference Monday afternoon that the shooter was among the dead. Officials say the gunman has been identified as 34-year-old Aaron Alexis.
Earlier in the day, authorities had been looking for two other people who may have been involved in the shooting. One of those people has been identified and ruled out as a suspect.