Report: Pentagon must focus on insider threat

WASHINGTON - An independent review triggered by the Washington Navy Yard killings last year says threats to Defense Department personnel and facilities increasingly are coming from within.

It says the department must rethink its outdated security theory that suggests defending the perimeters can keep threats away. Instead, it says that terrorism, espionage and even physical threats are coming from trusted insiders.

The report recommends cutting the number of workers who hold security clearances, conducting better and routinely updated background checks, and setting up a system to evaluate and handle employees who may pose a threat.

Former Navy reservist Aaron Alexis gunned down 12 civilian workers in a Navy Yard building last September. Investigations found there were gaps in his security clearance review and that he had mental health issues that went undetected.