Sen. John Kerry, D-Mass., the chairman of the Senate Foreign Relations Committee, came to Rice's defense, calling her a "remarkable public servant" and saying that he was "deeply disturbed by efforts to find the politics instead of finding the facts in this debate. Everyone who cares about the four fallen Americans in Benghazi would do well to take a deep breath about what happened."

An accountability board appointed by Secretary of State Hillary Clinton should be allowed to do its work, he said in a statement directed specifically at King, adding, "We need to drop the politics and pull together and bring the killers of Chris Stevens and our fallen heroes to justice."

In their initial accounts, Rice and other senior administration officials insisted there was no indication the attack was “pre-planned.” It grew, they said, from a spontaneous protest outside the consulate that was inspired by the violent demonstration outside the U.S. Embassy in Cairo against a video denigrating the Prophet Mohammed, the founder of Islam. The video, which has triggered a rash of violent anti-American protests across the Middle East, North Africa and South Asia, was made in the United States.

The accounts, however, were quickly challenged. President Mohammad Magarief, the head of the Libyan National Congress, the recently elected interim government, said that the assault was organized and planned by foreigners, some with links to al Qaida, involved members of a local Islamist militant group, and was deliberately timed for the anniversary of 9/11.

Witnesses corroborated Magarief’s account in interviews with McClatchy, saying there was no protest before the attack, which they described as complex and well-organized.

Senior lawmakers also questioned the administration’s version.

“It is my conclusion that it was a planned, coordinated event,” House Intelligence Committee Chairman Mike Rogers, R-Mich., told McClatchy in an interview.

Senior Republican lawmakers cited the differences in questioning the administration account as well as the security around the consulate. They pointed out that Americans in Libya were known to have been under threat, Benghazi had seen a rash of attacks on foreign targets by Islamist militants, and the country remains haunted by armed groups nearly a year after the U.S.-backed ouster of the late dictator Moammar Gadhafi.

Appearing before a Senate committee on Sept. 19, Matthew Olsen, the director of the National Counterterrorism Center, became the first senior administration official to publicly confirm that Stevens and the three other Americans died in a terrorist attack.

It took another day before White House Press Secretary Jay Carney said that it was “self-evident that what happened in Benghazi was a terrorist attack.”

Obama, facing a tough re-election campaign, has refrained from calling the incident a terrorist attack even as he decried the incident and the deaths of the Americans before the U.N. General Assembly on Tuesday.

Pressed on Wednesday by reporters on why Obama hasn’t used the term, Carney replied, “It is certainly the case that it is our view as an administration, the president’s view, that it was a terrorist attack.”