Weighing the decision to remain or evacuate, a defense official told CNN, is "minute by minute, hour by hour."
American military assets have been pre-positioned at a naval base in Sigonella, Italy. The eight V-22 Osprey aircraft and 200 Marines stationed in Moron, Spain -- part of the Marine Air-Ground Task Force Crisis Response Team that was stood up after the 2012 attack on U.S. Consulate Benghazi -- could be called upon to help evacuate the embassy, the official said.
Militia members opposed to Islamist control of the Libyan government overtook the Libyan parliament building, prompting large-scale unrest in the capital.
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