WASHINGTON (AP) — Defense Secretary Chuck Hagel has 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.

Two days after former Navy reservist Aaron Alexis gunned down 12 people in a shooting rampage inside the Navy base, Pentagon leaders struggled with whether a string of minor arrests, mental health issues and other behavioral problems should have been enough to strip him of his security clearance or deny him access to the secure facility in southeast Washington.