(AP)  Aaron Alexis seems a study in contradictions: a former Navy reservist, a Defense Department contractor, a convert to Buddhism who was taking an online course in aeronautics. But he also had flashes of temper that led to run-ins with police over shootings in Fort Worth, Texas, and Seattle.

A profile began to emerge of the man authorities identified as the gunman in yesterday's mass shooting at the Navy Yard in Washington, D.C., that left 13 people dead, including the 34-year-old man. While some neighbors and acquaintances described him as "nice,'' his father once told detectives in Seattle his son had anger management problems related to post-traumatic stress brought on by the terrorist attacks of September 11th, 2001. He also complained about the Navy and being a victim of discrimination.

FBI website

Find out more about the shooting HERE.