Gunmen who killed 12 in Washington ‘heard voices in his head’

But the navy had not declared Aaron Alexis, a 34, mentally unfit, which would have rescinded a security clearance.

WASHINGTON // The former navy reservist who killed 12 people at the Washington Navy Yard had been hearing voices and was being treated for mental illness in the weeks before the shooting rampage, but was not stripped of his security clearance, officials said on Tuesday.

Aaron Alexis, a 34-year-old information technology employee with a defence contractor, used a valid pass to get into the highly secure installation Monday morning and started firing inside a building, the FBI said. He was killed in a gun battle with police.

The motive for the mass shooting — the deadliest on a military installation in the US since the attack at Fort Hood, Texas, in 2009 — was a mystery, investigators said.

US law enforcement officials said there was no known connection to terrorism and that investigators have found no manifesto or other writings suggesting a political or religious motive.

Alexis had been suffering a host of serious mental problems, including paranoia and a sleep disorder, and had been hearing voices in his head, according to the officials.

He had been treated since August by Veterans Affairs, the officials said.

The navy had not declared him mentally unfit, which would have rescinded a security clearance Alexis had from his earlier time in the naval reserves.

The assault is likely to raise more questions about the adequacy of the background checks done on contract employees and others who are issued security clearances — an issue that came up most recently with National Security Agency leaker Edward Snowden, an IT employee with a government contractor.

In the hours after the Navy Yard attack, a profile of Alexis began coming into focus.

A Buddhist convert who had also had flare-ups of rage, Alexis, who grew up in New York City and whose last known address was in Fort Worth, Texas, complained about the navy and being a victim of discrimination. He also had run-ins with the law over shootings in 2004 and 2010 in Texas and Seattle, and was ticketed for disorderly conduct after being thrown out of a metro Atlanta nightclub in 2008.

Alexis’ bouts of insubordination, disorderly conduct and being absent from work without authorisation prompted the navy to grant him an early — but honourable — discharge in 2011 after nearly four years as a full-time reservist, authorities said. During his service, he repaired aircraft electrical systems at Fort Worth.

In addition to those killed at the Navy Yard attack, eight people were hurt, including three who were shot and wounded, authorities. Those three were a police officer and two female civilians, authorities said. They were all expected to survive.

The dead ranged in age from 46 to 73, officials said. A number of the victims were civilian employees and contractors, rather than active-duty military personnel.

Monday’s onslaught at a single building at the Navy Yard unfolded about 8:20am in the heart of the nation’s capital, less only a few kilometres from the White House and the Capitol. It put all of Washington on edge.

“This is a horrific tragedy,” Mayor Vincent Gray said.

Law enforcement officials said Alexis used a shotgun and two handguns, but not an AR-15 assault rifle, as authorities previously reported. He bought the shotgun and took the handguns away from law officers at the scene, an official said.

For much of the day Monday, authorities said they were looking for a possible second attacker who may have been disguised in an olive-drab military-style uniform. But by late Monday night, they said they were convinced the shooting was the work of a lone gunman, and the lockdown around the area was eased.

“We do now feel comfortable that we have the single and sole person responsible for the loss of life inside the base today,” Washington Police Chief Cathy Lanier said.

The FBI took charge of the investigation.

The attack came four years after Army psychiatrist Maj Nidal Hasan killed 13 people at Fort Hood in what he said was an effort to save the lives of Muslims overseas. He was convicted last month and sentenced to death.

At the time of the rampage, Alexis was an employee with The Experts, a company that was a Defence Department subcontractor on a computer project, authorities said.

Associated Press