Dozens of operatives working for the Central Intelligence Agency were on the ground in Benghazi on the night of a Sept. 11, 2012 attack upon a U.S. consulate post that left Ambassador Christopher Stevens and three others dead, CNN reported Thursday:
CNN has learned the CIA is involved in what one source calls an unprecedented attempt to keep the spy agency's Benghazi secrets from ever leaking out.
Since January, some CIA operatives involved in the agency's missions in Libya, have been subjected to frequent, even monthly polygraph examinations, according to a source with deep inside knowledge of the agency's workings.
The goal of the questioning, according to sources, is to find out if anyone is talking to the media or Congress.
It is being described as pure intimidation, with the threat that any unauthorized CIA employee who leaks information could face the end of his or her career.
A CIA spokesman issued a statment saying the agency has been transparent with Congress as to the details of the attack.
"The CIA has worked closely with its oversight committees to provide them with an extraordinary amount of information related to the attack on U.S. facilities in Benghazi," the statement said.