Charlene Lamb is the one that spilled the beans. Charlene Lamb from her testimony before the House Oversight Committee, October 10, 2012.
"When the attack began, a Diplomatic Security agent working in the Tactical Operations Center immediately activated the Imminent Danger Notification System and made an emergency announcement over the PA. Based on our security protocols, he also alerted the annex U.S. quick reaction security team stationed nearby, the Libyan 17th February Brigade, Embassy Tripoli, and the Diplomatic Security Command Center in Washington. From that point on, I could follow what was happening in almost real-time.”
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