Al Qaeda, other terrorist groups reacting to leaks, changing tactics

U.S. intelligence agencies are scrambling to salvage their surveillance of Al-Qaida and other terrorist groups who are working frantically to change how they communicate after a National Security Agency contractor leaked details of surveillance programs.

It's an electronic game of cat-and-mouse that can have deadly consequences if a plot is missed or a terrorist operative manages to drop out of sight.

Two U.S. intelligence officials say members of virtually every terrorist group, including core al-Qaida, are attempting to change how they communicate, based on what they're reading in the media, to hide from U.S. spies. It's the first time intelligence officials have described which groups are reacting to the leaks.

The officials spoke anonymously because they were not authorized to speak about the intelligence matters publicly.