The Obama administration neglected to convene its “top interagency counterterrorism resource: the Counterterrorism Security Group (CSG)” during the deadly terrorist attack on the U.S. Mission in Benghazi, sources tell CBS News.

Citing “top counterterrorism sources,” CBS reports there was internal frustration over the U.S. response to the coordinated attack in Libya on 9/11. The fiery assault that resulted in the deaths of U.S. Ambassador Chris Stevens and three other Americans lasted about seven hours.

CBS Sources: Key Counterterrorism Task Force Not Convened During Benghazi Attack

A vehicle and the surrounding area are engulfed in flames after it was set on fire inside the US consulate compound in Benghazi late on September 11, 2012. (Credit: AFP/Getty Images)

“The CSG is the one group that’s supposed to know what resources every agency has. They know of multiple options and have the ability to coordinate counterterrorism assets across all the agencies…They were not allowed to do their job. They were not called upon,” a high-ranking U.S. official told CBS News. More from the report:

The circumstances of the attack, including the intelligence and security situation there, will be the subject of a Senate Intelligence Committee closed hearing on Nov. 15, with additional hearings to follow.

Counterterrorism sources and internal emails reviewed by CBS News express frustration that key responders were ready to deploy, but were not called upon to help in the attack.

CBS News has agreed not to quote directly from the emails, and to protect the identities of the sources who hold sensitive counterterrorism posts within the State Department, the US military and the Justice Department.

As to why the Counterterrorism Security Group was not convened, National Security Council Spokesman Tommy Vietor told CBS News “From the moment the President was briefed on the Benghazi attack, the response effort was handled by the most senior national security officials in governments. Members of the CSG were of course involved in these meetings and discussions to support their bosses.”

An additional senior counterterrorism official told CBS News that a hostage rescue team was told to gear up, then to stand down repeatedly throughout the night, “as officials seemed unable to make up their minds,” according to the report.

(Related: Senior U.S. Officials: State Department Never Requested Military Backup in Benghazi)

The U.S. military’s Africa Command was also formulating an action plan as the attack was happening, however, nothing ever came from it.

“Forces were positioned after the fact but not much good to those that needed it,” a military official told CBS News.

Referring to the top brass in the executive branch, an intelligence official said the “response process was isolated at the most senior level…My fellow counterterrorism professionals and I (were) not consulted.”

“The Administration also didn’t call on the only interagency, on-call, short notice team poised to respond to terrorist incidents worldwide: the Foreign Emergency Support Team (FEST). FEST’s seasoned experts leave within four hours of notification and can provide ‘the fastest assistance possible,’” the report states.

CBS News points out that FEST teams were sent in immediately after al-Qaeda bombings in U.S. embassies in East Africa in 1988and the USS Cole in 2000. Officials speculate that the CSG task force, if they were consulted, would have recommended FEST intervention.

“First a tactical response was needed,” a senior U.S. counterterrorism official said, “and while that was being implemented, the holistic response could have been developed and deployed within hours.”

To read CBS News’ full report, click here.