WASHINGTON (AP) — U.S. law enforcement officials say that the Navy contractor identified as the gunman in the mass shootings at the Washington Navy Yard had been suffering a host of serious mental issues, including paranoia and a sleep disorder.
He also had been hearing voices in his head, the officials said.
Aaron Alexis, 34, had been treated since August by the Veterans Administration for his mental problems, the officials said.
They spoke on condition of anonymity because the criminal investigation in the case was continuing.
The Navy had not declared him mentally unfit, which would have rescinded a security clearance that Alexis had from his earlier time in the Navy Reserves.
Family members told investigators that Alexis was being treated for his mental issues.
Also, U.S. officials said Tuesday that Alexis had a string of misconduct problems during his nearly three years in the military, but he received an honorable discharge.
Alexis had bouts of insubordination, disorderly conduct and was sometimes absent from work without authorization. The offenses occurred mainly while he was serving in Fort Worth, Texas, from 2008-2011, and were enough to prompt Navy officials to grant him an early discharge through a special program for enlisted personnel.
Officials said the bad conduct was enough to make it clear that Alexis would not be a good sailor but not enough to warrant a general or less-than-honorable discharge.
Meanwhile, the deadly attack at the Washington Navy Yard was carried out by one of the military's own: a defense contract employee and former Navy reservist who used a valid pass to get onto the installation and started firing inside a building, killing 12 people before he was slain in a gunbattle with police.
The motive for the mass shooting — the deadliest on a military installation in the U.S. since the tragedy at Fort Hood, Texas, in 2009 — was a mystery, investigators said. But a profile of the lone gunman, Alexis, was coming into focus. He was described as a Buddhist who had also had flare-ups of rage, complained about the Navy and being a victim of discrimination and had several run-ins with law enforcement, including two shootings.
Monday's onslaught at a single building at the highly secure Navy Yard unfolded about 8:20 a.m. EDT in the heart of the nation's capital, less than four miles from the White House and two miles from the Capitol.
It put all of Washington on edge. Mayor Vincent Gray said there was no indication it was a terrorist attack, but he added that the possibility had not been ruled out.
“This is a horrific tragedy,” he said.
Alexis carried three weapons: a shotgun and two handguns, according to two federal law enforcement officials who spoke on condition of anonymity because they were not authorized to discuss the investigation.
Law enforcement officials said Tuesday that Alexis did not use an AR-15 assault rifle, as officials previously said.
Two law enforcement officials told The Associated Press that an AR-15 was found at the scene. One of them said Tuesday that Alexis did not use that weapon in the shootings.
It was not immediately clear whether the rifle belonged to a law enforcement or security officer responding to the gunbattle.
The official said Tuesday that the guns that Alexis used included a shotgun he had purchased and two handguns that he took away from law enforcement officer at the scene.
For much of 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 that 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.
President Barack Obama lamented yet another mass shooting in the U.S. that he said took the lives of American “patriots.” He promised to make sure “whoever carried out this cowardly act is held responsible.”
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.
In addition to those killed at the Navy Yard, eight people were hurt, including three who were shot and wounded, according to the mayor. 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, according to the mayor. A number of the victims were civilian employees and contractors, rather than active-duty military personnel, the police chief said.
At the time of the rampage, Alexis was an employee with The Experts, a company that was a Defense Department subcontractor on a Navy-Marine Corps computer project, authorities said.
Valerie Parlave, head of the FBI's field office in Washington, said Alexis had access to the Navy Yard as a defense contractor and used a valid pass.
Alexis had been a full-time Navy reservist from 2007 to early 2011, leaving as a petty officer third class, the Navy said. It did not say why he left. He had been an aviation electrician's mate with a unit in Fort Worth.
A convert to Buddhism who grew up in New York City, Alexis had had run-ins with the law over shooting incidents in 2004 and 2010 in Fort Worth and Seattle and was portrayed in police reports as seething with anger.
The Washington Navy Yard is a sprawling, 41-acre labyrinth of buildings and streets protected by armed guards and metal detectors, and employees have to show their IDs at doors and gates. More than 18,000 people work there.
The rampage took place at Building 197, the headquarters for Naval Sea Systems Command, which buys, builds and maintains ships and submarines. About 3,000 people work at headquarters, many of them civilians.
Witnesses on Monday described a gunman opening fire from a fourth-floor overlook, aiming down on people on the main floor, which includes a glass-walled cafeteria. Others said a gunman fired at them in a third-floor hallway.
As emergency vehicles and law enforcement officers flooded the streets, a helicopter hovered, nearby schools were locked down and airplanes at Reagan National Airport were grounded so they would not interfere with law-enforcement choppers.
Security was tightened at other federal buildings. Senate officials shut down their side of the Capitol. The House remained open.
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