WASHINGTON (AP) -- The Washington Navy Yard gunman visited two hospitals in the weeks before the rampage but did not say he was depressed or having thoughts of harming himself or others, the Veterans Affairs Department said Wednesday.
Aaron Alexis, a former Navy reservist who killed 12 people Monday before being slain in a police shootout, complained of insomnia during an Aug. 23 emergency room visit at the VA Medical Center in Providence, R.I. He was given sleep medication and was advised to follow up with a doctor. He made a similar visit five days later to the VA hospital in Washington, when he again complained of not being able to sleep because of his work schedule. His medication was refilled.
The VA's statement comes as investigators continue focusing on the mental state of a 34-year-old man who law enforcement officials say was grappling with paranoia and reported hearing voices and being followed.
Two weeks before his ER visit, for instance, he complained to police in Rhode Island that people were talking to him through and the walls and ceilings of his hotel room and sending microwave vibrations into his body to deprive him of sleep. Newport police alerted the naval station, and they did not hear from again.
Despite the apparent concerns over his mental health and past run-ins with the law, Alexis maintained his security clearance as he arrived in Washington in late August for a position as an information technology employee at a defense-related computer company.
He used a valid badge to gain access to the sprawling Navy Yard and Building 197, bringing with him a shotgun bearing the cryptic messages of "better off this way" and "my ELF weapon," according to a law enforcement document reviewed by The Associated Press. The meaning of those words wasn't immediately clear.
The motive of the shooting remains unclear, though investigators have focused on Alexis's mental health and alarming behavior displayed in the weeks before the massacre.
Alexis had enrolled in VA health care in February 2011, and received monthly disability payments of $395 for orthopedic problems and ringing in his ears.
Meanwhile, Alexis's mother said Wednesday she does not know why her son opened fire and on office workers during a more than 30-minute rampage and shootout with police.
Cathleen Alexis read a brief statement inside her New York home, her voice shaking. She did not want to appear on camera and did not take questions from a reporter.
"Aaron is now in a place where he can no longer do harm to anyone, and for that I am glad," Cathleen Alexis said. "To the families of the victims, I am so so very sorry that this has happened. My heart is broken."
Authorities say Alexis had with him during the massacre a handgun he picked up from an officer inside the building and a legally obtained Remington 870 Express shotgun - a firearm that would not be covered under a proposed weapons ban supported by the White House. The ban was introduced in the Senate earlier this year and would prohibit 157 specific firearms designed for military and law enforcement use, and it would exempt more than 2,200 others.
The Navy Yard was set to return to mostly normal operations Thursday, although Building 197 and the gym, which is being used as a staging area for the FBI, will remain closed.
The shooting, which police still don't have a motive for, raised questions about the adequacy of background checks for government contractors who have access to sensitive information. Navy Secretary Ray Mabus this week ordered two security reviews of how well the Navy protects its bases.
Defense Secretary Chuck Hagel has also ordered two sweeping reviews of military security and employee screening programs, acknowledging Wednesday that "a lot of red flags" may have been missed in the background of the Washington Navy Yard shooter.
"Obviously, there were a lot of red flags," Hagel told reporters at a Pentagon briefing. "Why they didn't get picked, why they didn't get incorporated into the clearance process, what he was doing, those are all legitimate questions that we're going to be dealing with."
Associated Press writers Kevin Freking, Alicia A. Caldwell and Eileen Sullivan in Washington contributed to this report.