H  STATE LAW STOPPED GUNMAN FROM BUYING ASSAULT RIFLE, OFFICIALS SAY 

S1  With: DC-SHOOTING, DC-SHOOTING-VICTIMS);

S2  WASHINGTON - The gunman who killed 12 people at the Washington Navy Yard on Monday test fired an AR-15 assault rifle at a Virginia gun store last week and tried to buy one but was prevented from doing so because Virginia state law prohibits the sale of such weapons to out-of-state buyers, according to two senior law enforcement officials.

S3  Instead, the gunman, Aaron Alexis of Texas, bought a law-enforcement-style shotgun - an 870 Remington pump - and used it Monday as he rampaged through the Navy facility, said the officials, who requested anonymity because of the continuing investigation.

S4  “The gun was broken in half, and he had it in a bag,” one official said of the Remington.
S5 “He went inside the building and assembled it in a bathroom.”

S6  The gunman then perched himself above an atrium where he fired down on people who had been eating breakfast.
S7 He used shotgun shells that had roughly a dozen large ball-bearing-like shots in them, increasing the lethal nature of each shot.

S8  “When he discharged, the pieces of lead would spread the farther they went,” the official said.
S9 “It is similar to weapons used in bird shooting but on a more serious scale.
S10 These were not bullets but many small pieces of lead flying through the air.”

S11  After firing down on the people, the gunman began to search for more people to shoot, according to the law enforcement officials.
S12 As he searched, he was confronted by a security guard near an exit.
S13 The gunman shot the security guard and took his semiautomatic handgun, then headed back to atrium.

S14  “He runs back upstairs and cranks off more rounds with the handgun and then heads to another stairwell where he confronts a worker there and shoots him,” one of the officials said.

S15  The gunman is believed to have shot the Navy employee, who worked in maintenance, with the pistol near another exit.

S16  The most recent account from the law enforcement officials was based on hundreds of interviews that investigators conducted over the past day and hours of video footage analyzed by FBI agents and analysts.

S17  Despite statements from senior law enforcement officials Monday that an AR-15 had been found at the scene, no such gun has been found, and the authorities say they do not believe the gunman used one.

S18  It is unclear if Alexis’ psychiatric issues ever progressed to the point that he was involuntarily committed to a mental health institution, or determined officially to be mentally ill, either of which would have barred him from purchasing a gun.

S19  If neither applied - and most people who are treated for mental illness never get to that point - then his situation would be similar to other mass shooters, like Jared L. Loughner, who killed six people and wounded 12, including former Rep. Gabrielle Giffords, in Tucson, Ariz., in 2011, and James E. Holmes, who killed 12 people and wounded dozens of others in a Colorado movie theater in 2012.

S20  Mental health experts point out that the vast majority of people with mental illness are never violent.
S21 On the other hand, studies have found an increased risk for violence among those with serious mental illness, including schizophrenia, major depression or bipolar disorder.

