Report: Yemeni al-Qaida members took part in Benghazi attack WASHINGTON, May 2 (UPI) -- Yemeni members of an al-Qaida branch participated in the attack on a diplomatic mission in which the U.S. ambassador to Libya was killed, a U.S. official said. Citing several sources it did not identify, CNN reported Thursday "three or four members of al-Qaida in the Arabian Peninsula" took part in the Sept. 11, 2012, attack in Benghazi, Libya, in which Ambassador Christopher Stevens and three other U.S. citizens were killed. A second source CNN said had been briefed on the Benghazi investigation said Western intelligence agencies suspect AQAP may have sent the men to Libya to carry out the attack but have not ruled out the possibility the men were in Benghazi before the attack and simply took part once it began. A senior law enforcement source said counter-terrorism officials tracked the men to northern Mali, where they are suspected of having joined up with a group of fighters headed up by Algerian terrorist Moktar Belmoktar but no sign of the men has been seen since then. Belmoktar has claimed responsibility for the January attack on the In Amenas gas facility in Algeria in which 38 people were reported killed.