Washington:
Ex-CIA chief David Petraeus began his testimony before lawmakers on Friday about the September 11 assault on the US mission in Benghazi, his first appearance since resigning suddenly a week ago.
Packs of reporters and camera crews were on hand at the US Capitol hoping to catch Petraeus entering the highly-anticipated, closed-door hearing of the House Intelligence Committee but they were left disappointed.
The retired general was escorted through a side door, a staffer said, and lawmakers who used the main entrance declined to discuss what they hoped to hear from Petraeus, who is embroiled in scandal over an extra-marital affair.
Republicans have blasted the White House over its response to the Benghazi attack -- which killed the US ambassador and three other Americans -- and its initial conflicting explanations of what happened, hinting at a wider cover-up.
The mission in Benghazi, Libya included a CIA operation, which Petraeus would have overseen before quitting as spy chief last week over his affair with biographer Paula Broadwell, which was uncovered by the FBI.
Republicans have accused Washington's UN envoy Susan Rice of misleading the country by telling Sunday talk shows after the attack that it was part of a "spontaneous" protest against an anti-Islam video.
It eventually emerged that there was no protest, but rather a coordinated assault on the compound believed to have been carried out by Al-Qaeda-linked Ansar al-Sharia militants.
Petraeus will testify at two closed-door hearings on Friday, and according to CNN will say he knew "almost immediately" that Ansar al-Sharia was behind the attack, but that there was "confusion" about the assault.
The retired four-star general will also reportedly say that 20 intelligence reports linked the attack to the video, which sparked violent protests the same day in Cairo, where demonstrators scaled the walls of the US embassy.
Several congressional hearings, most of them closed to the public, are probing the Benghazi killings this week. A heated House hearing Thursday saw lawmakers exchange bitter accusations about the assault and the White House's handling of it.
State Department and FBI probes into the attack are also currently under way, and Secretary of State Hillary Clinton has agreed to testify before House and Senate hearings once her department finishes a review of events in Benghazi. That report is expected by mid-December.
US senators got their first look on Thursday at dramatic real-time video footage of the attack.
However, the hearings seem to have done little to resolve the partisan sparring over the administration's response, with Republicans strongly hinting at a larger scandal and President Barack Obama's fellow Democrats appearing more reassured.
The deputy chairman of the Senate Intelligence Committee, Republican Senator Saxby Chambliss, said the hearing with US intelligence officials Thursday made clear that "mistakes were made."
Chambliss said there would eventually be public hearings and "the American people are going to have the opportunity to see the questions asked and get the answers to questions that they have had since September 11th of this year."
Republican Senator Roy Blunt told CNN that, based on the video of the hours-long consulate attack, "it's not hard to establish that there was no demonstration, there was no crowd.
"When this started, it started as an act of violence. And that should have been obvious to anybody talking about that from the very start," Blunt added.
But Democrat Adam Schiff said after a House Intelligence Committee hearing that acting CIA director Michael Morell told the panel Rice was briefed with the same unclassified information that lawmakers received.
Schiff said those who suggest Rice was "misrepresenting" intelligence "are either unfamiliar with the facts, or willfully disregarding them."
Critics have seized on Rice's remarks to argue that the White House misled or even lied to Americans during a heated election season.
Rice has been floated as a possible successor to Clinton, who is stepping down early next year, but some Republicans have threatened to block her appointment over Benghazi.
Obama has accepted responsibility for any failings related to the attack and on Wednesday scolded Republicans for going after Rice.
The inquiry into Benghazi has been further complicated by the downfall of Petraeus, who resigned after his affair was uncovered by an FBI investigation into threatening emails sent by Broadwell to Florida socialite Jill Kelley, whom she apparently viewed as a competitor for the general's affections.
The investigation also uncovered a trove of correspondence -- some described as "flirtatious" -- between Kelley and General John Allen, Petraeus's successor as the top US commander in Afghanistan.
The married Allen -- whose promotion to NATO commander in Europe has been held up over the probe -- says he has never been in the same room alone with Kelley, who is also married and was a family friend of both Petraeus and Allen.