Shortly before 10 p.m., Secretary of State Hillary Clinton is notified. She speaks to Libyan President Mohammed Magariaf to enlist his support.
About 10 p.m., as several State Department diplomatic security agents gather tactical gear elsewhere, agent Scott Strickland moves Ambassador Chris Stevens and information officer Sean Smith to a safe room in Building C. The other agents come under attack and the attackers set fire to Building C. Stevens, Smith and Strickland move to the bathroom, but decide to leave because of the smoke. Strickland goes out an emergency escape window. Stevens and Smith do not follow. Strickland returns but can't find them in the smoke. He radios the other agents.
About 10:25, three agents return to Building C via armored vehicle. They find Smith's body, but not Stevens. The group falls back to the CIA annex.
About 11 p.m., National Security Adviser Tom Donilon advises President Obama of the attack while he was meeting with Defense Secretary Leon Panetta and the chairman of the Joint Chiefs of Staff, Gen. Martin Dempsey. Obama orders that the U.S. begin moving military assets into the region to prepare for a range of contingencies.
About midnight, agents arrive at the annex, which receives sporadic small-arms fire and RPG rounds over 90 minutes.
About 12:30 a.m., the Pentagon issues an order to a special operations team in Europe to move to Sigonella, Sicily -- less than one hour's flight away from Benghazi. Over the next three hours a U.S-based team is deployed to Sigonella. Neither arrived in time.
1 a.m., first of two unarmed U.S. Predator drones is diverted to Benghazi.
1:30 a.m., a U.S. security team from the embassy in Tripoli lands in Benghazi. They try to arrange for transportation into town, with the goal of locating Stevens.
4:07 a.m., Clinton issues a statement acknowledging the death of one State Department officer.
5 a.m., second U.S. drone arrives.
5:15 a.m., the U.S. Regional Security Office in Tripoli gets a phone call from an Arabic-speaking source who says a Westerner, believed to be Stevens, has been found at a hospital.
About this time, an additional security team leaves the airport and goes to the annex. The annex takes mortar fire; CIA contractors Tyrone Woods and Glen Doherty, both former Navy SEALs, are killed. After the attack, about 30 Americans are moved from the annex to the airport.