Then, about 1 a.m., the siege went suddenly quiet, a pause that lasted until near daybreak, apparently leading CIA and State Department officials to think the danger had passed.
In the ‘‘pre-dawn time frame, that team at the airport finally manages to secure transportation and armed escort and — having learned that the ambassador was almost certainly dead — heads to the annex to assist with the evacuation,’’ the official said.
The team arrived, accompanied by Libyan security elements, at 5:15 a.m., ‘‘just before the mortar rounds begin to hit the annex,’’ the official said. Some mortar rounds struck the roof, where guards had taken position and returned fire.
Two CIA contractors, both former Navy SEALs, were killed. That final spasm of violence lasted 11 minutes, officials said. ‘‘Less than an hour later, a heavily-armed Libyan military unit arrived to help evacuate the compound of all US personnel,’’ the senior US intelligence official said.