The gunman who killed 12 people before being shot dead by police at the Washington Navy Yard had a history of violent outbursts, was at least twice accused of firing guns in anger, and was in the early stages of treatment for serious mental problems.
But Aaron Alexis, a 34-year-old military contractor and former Navy reservist, apparently managed to exploit loopholes in the nation's patchwork of complicated gun laws designed to keep weapons out of the hands of dangerous people. He was able to buy a shotgun in Virginia with out-of-state identification, even though that would have prevented him from buying a handgun.
Meanwhile, a picture emerged of Alexis as an agitated and erratic man whose behaviour and mental state repeatedly came to authorities' attention but apparently never affected his security clearance to do work for the Department of Defence.
Alexis, an information technology employee at a defence-related computer company, used a valid pass on Monday to get into the Navy Yard. Officials said besides being armed with the shotgun, he also took a handgun from a law officer. A day after the assault, the motive was still a mystery.
It is illegal for gun dealers to sell handguns to such out-of-state buyers, but the Firearms Owners' Protection Act, passed by Congress in 1986, opened up interstate sales for shotguns and rifles. Virginia gun laws require only that an out-of-state buyer show valid identification, pass a background check and otherwise abide by state laws in order to buy a shotgun in the state. Alexis was never prosecuted for two charges involving guns.
Alexis bought the shotgun at Sharpshooters Small Arms Range in Lorton, Virginia, on Saturday, according to a statement from the lawyer for the gun range. Michael Slocum said that Alexis rented a rifle, bought bullets and used the range before buying the shotgun and 24 shells. He said Alexis passed a background check.
Federal gun laws bar the mentally ill from legally buying guns from licenced dealers. But the law requires that someone be involuntarily committed to a mental health facility or declared mentally ill by a judge, and that information must be reported to the FBI in order to appear on background checks.
In the wake of the mass shooting at Virginia Tech in 2007, state authorities changed state laws to make it tougher for the mentally ill to buy guns there.
But Alexis was never declared mentally ill by a judge or committed to a hospital. He had been undergoing mental health treatment from the Department of Veterans Affairs since August but was not stripped of his security clearance. He suffered serious mental problems, including paranoia and a sleep disorder and had been hearing voices in his head, officials said, but he was not stripped of his security clearance.
He had been suffering from a host of serious mental problems, including paranoia and a sleep disorder, and had been hearing voices in his head, the officials said.