While the evacuation from Benghazi was being planned by the embassy and the CIA, Ham said, he switched his focus toward gearing up a possible hostage rescue mission, because the ambassador was still missing.
Meanwhile, surviving U.S. personnel were gathered at the CIA base in Benghazi. Ham said he believed they were relatively safe. He and other military leaders said they weren't told that the CIA compound already had come under gunfire and rocket-propelled grenade attacks in the middle of the night.
The U.S. security team that arrived at the Benghazi airport after midnight was detained by Libyan officials for several hours. That delayed the evacuation, Ham said, and "allowed sufficient time for the second attack to be organized and conducted."
During that attack, around 5 a.m., mortar fire killed two CIA security contractors on the roof and wounded other Americans.
Less than an hour later, the evacuation of all American personnel from Benghazi began.
Associated Press writers Donna Cassata and Bradley Klapper contributed to this report.
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