US Defense Secretary Chuck Hagel has acknowledged that authorities missed some “red flags” that might have prevented the deadly mass shooting at the Washington Navy Yard.
Hagel made the admission as he announced details of a sweeping security review at all military bases in the aftermath of Monday’s attack that left 13 dead, including the gunman, at a naval installation in the heart of Washington.
“Obviously, when you go back in hindsight and look at all this, there were some red flags, of course there were,” Hagel said.
“And should we have picked them up? Why didn’t we? How could we have? All those questions need to be answered.”
The security review ordered by the Pentagon chief will examine physical security at military posts as well as the procedures for vetting outside contractors.
The security clearances issued by the government are under intense scrutiny after the shooting, as the alleged gunman, Aaron Alexis, had a valid pass as a defense subcontractor to enter the Navy Yard.
Alexis had the pass despite a record of misconduct in the Navy and run-ins with the law, including two shooting incidents and a Rhode Island police report showing he had severe delusions.
The security clearance was granted during his four-year stint as a sailor and remained in force once he left under an honourable discharge, according to the Navy.
Navy officials said none of his behaviour during his time as a naval reservist would have disqualified him for a security clearance, as he had not been convicted in a military or civilian court for a serious crime and his offences were not out of the ordinary.
Meanwhile, Alexis’ mother, Cathleen, has apologised on behalf of her son.
“To the families of the victims, I am so, so very sorry that this has happened. My heart is broken,” she said in a statement that she read from her Brooklyn, New York, home.
“Aaron is now in a place where he can no longer do harm to anyone, and for that am glad.
“I don’t know why he did what he did, and I’m never going to be able to ask him why.”