Via Reuters:

  The head of the National Security Agency told employees last month that NSA officials had not violated U.S. law by participating in an agency program that eavesdrops on U.S. citizens without judicial oversight, newly released documents show.
  "Media coverage surmises that administration and agency officials may have acted unlawfully — notions I reject, categorically!" NSA Director Lt. Gen. Keith Alexander assured agency employees in a December 22 message.
  He acknowledged that Congress may schedule hearings on the domestic spying program, which President George W. Bush authorized in 2002 to eavesdrop on Americans' telephone calls and e-mails without first obtaining warrants.
  "Overall, we are not concerned," the NSA director said. "Our operations are carefully deliberated and measured; they are within the law; and they are nobly executed with strict oversight."

  UPDATE: The message itself is available here, via EPIC. Thanks to Marcia Hofmann for the link.