Once a mob began attacking the U.S. Consulate in Benghazi, Libya, on the night of Sept. 11, officials in Washington, D.C., watched with alarm. Now, new details are emerging about their response to the deadly attack.

President Obama and his entire national security team monitored what was going on half a world away. Army Gen. Carter Ham, who was the regional commander for Africa, happened to be in Washington that day.

One source familiar with the events said there was a sense of urgency.

The consulate was burning, and Ambassador Chris Stevens, who was visiting the consulate with a small security team, was missing in the smoky chaos. For the next six hours or more, top officials in Washington watched and tried to send help as a second attack centered on the consulate's annex, a secret CIA base.

Officials say that U.S. forces from Europe and Fort Bragg in North Carolina were dispatched in an effort to help, but they arrived too late. Officials considered sending U.S. warplanes from Italy, but it was decided that dropping bombs would lead to civilian casualties.

Officials dispute a report on Fox News that there was a delay, a "stand down" for CIA operatives and Libyan guards to help those under fire at the consulate.

Could The U.S. Military Come To Their Aid?

The officials had little time to respond. There were no U.S. troops anywhere near the consulate, either in Libya or even in neighboring countries. So dozens of special operations forces and CIA guards from Tripoli were sent by aircraft to Benghazi, 480 miles to the east. They could not get there in time to help defend the consulate.

Ham, back in Washington, requested a military counterterrorism force from Europe. But they arrived in Libya the day after the attack and deployed to Tunisia two days later. A larger special operations force was sent from Fort Bragg, complete with their own helicopters and trucks. They arrived in Sigonella, Italy, too late to be any help. No American forces were denied by Washington, officials say.

American attack aircraft? An AC-130 gunship would seem to make sense. That's the lumbering black cargo plane, a flying battleship with three types of heavy guns and high-resolution cameras. It's often used to support special operations forces in tight urban areas and can zoom in on enemy forces. But there were no Spectre gunships in the area, officials learned.

Attack helicopters? None around. There were two Navy ships in the Mediterranean — the USS Laboon and the USS McFaul — but only the Laboon is equipped with a Seahawk helicopter, the Navy's version of the Black Hawk.

There were American warplanes based in Aviano, Italy, just across the Mediterranean, but they could not arrive in time to help with the consulate fight. When the attack began, consulate officials made an urgent call to the CIA guards at the nearby annex: We're under attack.

Was The Rescue Delayed?

The CIA official there organized his force and the Libyan guards at the annex. Some tried to find heavy machine guns to bring along to the consulate, about a mile away. One of the CIA operatives waiting to leave grew increasingly angry, convinced they were being told to "stand down" on two occasions, according to a report on Fox News.

CIA officials in Washington strongly deny there was any order not to mount a rescue mission. And the source tells NPR there was never an order to stay put. It was all about getting ready, not delaying. Within 24 minutes, the American and Libyan team moved out toward the consulate.

The convoy drove along an indirect route to avoid hostile militias, and the Americans and Libyans hustled along on foot for the last half mile, arriving an hour after the call for help.

The source said that surveillance cameras establish what time they left the annex and what time they showed up at the consulate. When they arrived, Ambassador Stevens was missing. He was carried to a hospital by looters, and later died there of asphyxiation from the smoke he inhaled while in the consulate's safe room.

The American and Libyan team loaded up the wounded and the survivors, and made their way back to the annex. They got lost in the maze of streets, and some militia members shot at their tires as they made it back to the annex. In Washington, there was relief. At the White House and the Pentagon, top officials believed the worst was over after the successful rescue mission.

The Second Attack

For several hours, there was a lull in the fighting. Then a second attack began, at the well-fortified annex. In Washington, the issue of attack aircraft came up among top officials.

The F-16 Fighting Falcons could come to the rescue from their base in Aviano, some officials thought. But there were no clear targets, it was decided. An unarmed Predator drone flew over the area, just before the consulate attack ended. But it offered only a "soda straw" view hundreds of feet below near the annex. There were no armed drones in the area.

Officials watched the grainy footage from the drone. It was hard to determine, among the hundreds of people, who was with a militia supporting the U.S., who was taking part in that second attack, and who was a spectator — people, as the source said, "watching a war movie in front of them." Sporadic gunfire added to the confusion about separating friend from foe.

Officials eventually decided they couldn't drop large bombs in a residential neighborhood.

A decision was made: no close air support, not even as a show of force that could possibly disperse the fighters. The Americans, and their Libyan allies fighting with them on the ground, were on their own.

At some point, the Quick Reaction Force arrived from Tripoli to help. Rocket-propelled grenades and mortars slammed into the annex. One mortar curled into the base and killed two Americans. The annex was never breached, and the attackers were fought off. The force from Tripoli helped move the survivors to the airport.

There was frustration in Washington that no more American firepower could be brought to help, according to the source. No more troops. No aircraft at all. If the Quick Reaction Force from Tripoli had not been able to fight off the attackers and evacuate the annex, there would have been even more casualties and perhaps more pressure to send in some type of additional American force.

In the end, four Americans were killed: Ambassador Stevens; Sean Smith, a U.S. Foreign Service officer; and two embassy security personnel, Glen Doherty and Tyrone Woods. Another 30 Americans and Libyans were wounded.

Obama and some of the same senior officials who huddled in Washington and tried to send them help assembled at Andrews Air Force Base three nights later to meet the four caskets.

Update at 6:45 a.m. ET, Nov. 2. Some Other News Outlets' Headlines:

-- "CIA Had Pivotal Part Fighting Attackers In Libya." (The New York Times)

-- "CIA Rushed To Save Diplomats As Libya Attack Was Underway." (The Washington Post)

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