Forty-nine minutes later, an email said that the firing at the consulate "has stopped and the compound has been cleared," while a response team was attempting to locate people.
The next message, one hour and 13 minutes after the second and some two hours after the attack began, a message reported that Ansar-al-Sharia claimed responsibility for the attack.
"Embassy Tripoli reports the group claimed responsibility on Faceboook and Twitter and has called for an attack on Embassy Tripoli," it said.
Nearly six hours after the initial attack, a State Department memo said the shelter location for the Americans was receiving mortar fire and "there are reports of injuries."
Ansar al-Sharia bragged to members of al-Qaida in the Islamic Maghreb that it was responsible for the attack, according to recordings of phone calls intercepted by U.S. intelligence. But the group has publicly denied having anything to do with the attack.
Clinton, speaking to reporters at the State Department, said, "You know, posting something on Facebook is not in and of itself evidence and I think it just underscores how fluid the reporting was at the time and continued some time to be."
She added, "What I keep in mind is that four brave Americans were killed and we will find out what happened, we will take whatever measures are necessary to fix anything that needs to be fixed and we will bring those to justice who committed these murders."
Associated Press writers Matthew Lee and Kimberly Dozier contributed to this story.
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