NSA Chief Claims That Leaks Have Changed Terrorists' Methods of Operation

Says leaks caused "significant, irreversible damage to our nation."

ASPEN, Colo., July 23 (UPI) — Terrorists have changed their methods of operation because of U.S. secrets leaker Edward Snowden's disclosures, the National Security Agency director said.

"We have concrete proof that they have already—terrorists groups and others—are taking action, making changes, and it's going to make our job tougher," Army Gen. Keith Alexander told a moderator from NBC News at the Aspen Security Forum in Colorado.