CIA officers revealed a clash over how quickly they should go help the besieged U.S. ambassador during the 2012 attack on an outpost in Libya, and a standing order for them to avoid violent encounters, according to a congressman and others who heard their private congressional testimony or were briefed on it.

The Obama administration has been dogged by complaints that the White House, Pentagon and State Department may not have done enough before and during the attack to save U.S. Ambassador Chris Stevens and three others, and by accusations that it later engaged in a cover-up.

One allegation was that U.S. officials told the CIA to “stand down” and not go to the aid of the Americans. Top CIA and Defense and State Department officials have denied that.

The testimony from the CIA officers and contractors who were in Libya on the night of Sept. 11, 2012, bolster those denials, but also shed light on what may have led to the delay of up to 30 minutes to respond, according to the varying accounts.

None of those who testified said a quicker response would have saved the lives of Stevens and communications specialist Sean Smith at the temporary diplomatic facility.

The senior CIA officers in charge in Libya that day told Congress of a chaotic scramble to aid Stevens and others who were in the outpost when it was attacked by militants on the 11th anniversary of the attacks of Sept. 11, 2001.

Those CIA leaders decided they and their security contractor team should wait before rushing from their annex into the violence roughly a mile away. They said they were trying to first gather intelligence and round up Libyan militia allies armed with heavy weapons, according to the testimony by the CIA officers in charge.

Some CIA security contractors disagreed with their bosses and wanted to move more quickly.

Rep. Lynn Westmoreland, who heads a House intelligence subcommittee that interviewed the employees, said he believes this disagreement was the source of allegations that the CIA ordered security personnel to “stand down” and not help the people inside the diplomatic mission, and perhaps was the source of accusations the administration failed to answer a call from the CIA security team for combat aircraft.

“The team leader knew he was on his own,” said Westmoreland, R-Ga.

He explained that the lack of air support was clear to all CIA employees working in Libya because of a 2011 CIA memorandum sent to employees after NATO forces ended their mission in support of the Libyan revolution.

“It basically told people in Benghazi … if you are attacked, you get your ‘package’ (the personnel they are charged with protecting) and you get out,” he said in an interview.

A senior intelligence official confirmed that the CIA officers on the ground in Benghazi responded to the diplomats’ call for help by trying “to rally local support for the rescue effort and secure heavier weapons.” When it became “clear that this additional support could not be rapidly obtained,” the team moved toward the diplomatic compound.

Westmoreland said the CIA security contractors loaded into two vehicles, with weapons ready, the moment they heard the radio call for help from the diplomatic building. Some wanted to rush to the U.S. compound roughly a mile away, and their agitation grew as they heard increasing panic when the diplomats reported the militants were setting the compound on fire.

None of those who testified would say they believed the ambassador or the others could have been saved had they arrived any faster, according to two officials, who also were briefed on the testimony.

When the seven CIA employees reached the diplomatic compound, they fought their way in and found the five State Department security personnel who had taken shelter in various parts of the compound.

They found computer specialist Smith, dead from smoke inhalation, but couldn’t find Stevens and decided to fall back to the CIA annex, because the crowd was building outside again, Westmoreland and the other officials said.

Stevens was found in a safe room and taken by Libyan civilians to a nearby hospital, but he died from smoke inhalation.

The CIA team believes their convoy was followed back to their compound, where they were first attacked by small arms fire around midnight local time, which quickly stopped when the CIA team returned fire, Westmoreland said.

Roughly five hours later, the CIA team testified that mortars hit, killing former Navy SEAL Tyrone Woods, who had helped rescue the diplomats, and former SEAL Glenn Doherty, who had just arrived with a team from Tripoli.