Lawmakers 'suspicious' administration 'trying to hide' Libya attack details Fresh claims that U.S. intelligence officials knew practically from the start that the attack on the U.S. Consulate in Benghazi was terrorism possibly tied to Al Qaeda have lawmakers alleging they were misled and questioning whether the administration has something to hide. "This is turning into something not short of Benghazi-gate," Sen. Bob Corker, R-Tenn., told Fox News, adding he's "very suspicious" about the way the administration has handled this. Two senior U.S. officials told Fox News on Thursday that U.S. intelligence officials knew within 24 hours of the assault that it was a terrorist attack and suspected Al Qaeda-tied elements were involved. The account sharply conflicted with claims by U.S. Ambassador to the United Nations Susan Rice on the Sunday after the attack that the administration believed the strike was a "spontaneous" event triggered by protests in Egypt over an anti-Islam film. "The best information and the best assessment we have today is that in fact this was not a preplanned, premeditated attack -- that what happened initially was it was a spontaneous reaction to what had just transpired in Cairo as a consequence of the video," Rice said on "Fox News Sunday" at the time. Rep. Mac Thornberry, R-Texas, a member of the House intelligence committee, said that's consistent with what lawmakers were told in briefings. "If there was information a day after that was to the contrary, I think Congress was misled," Thornberry told Fox News. But again, it's even more serious than that. It means that we have a real problem in not being able to face up to the national security challenges our country faces. Corker also said a briefing he and his colleagues received was "worthless," and he demanded "answers" about the changing story. "This has now turned into a very bipartisan concern," he said. There has to be something that they're trying to hide or cover up. ... This is just not the norm. This is way out of the norm, what is happening in this case. Democratic and Republican lawmakers on the Senate Foreign Relations Committee, on which Corker sits, sent a letter to the State Department Thursday asking a string of new questions about security at U.S. diplomatic posts. President Obama's aides have denied any attempt to cover things up. "No one either intentionally or unintentionally misled anyone involved in this," campaign adviser Robert Gibbs said on "Fox News Sunday." Rice was the most explicit in that explanation, insisting in those Sunday shows that the attack was not pre-planned and was tied to the film. Defense Secretary Leon Panetta was the latest Thursday to declare: "It was a terrorist attack." That's the group that, according to senior officials, the intelligence community suspected by Sept. 12, the day after the attack, of being involved -- along with the militant Ansar al-Shariah. Officials also confirmed they had several "intelligence assets" on the ground to track Ansar al-Shariha and Al Qaeda in the Islamic Maghreb. They said the attack was labeled as terrorism from the start in order to free up certain resources. Specifically, it was labeled under the "Authorization for the Use of Military Force Against Terrorists" category, created by a post-9/11 congressional action. White House Press Secretary Jay Carney also said that Obama now believes it was terrorism as well. Yet a congressional source told Fox News that CIA Director David Petraeus, during a briefing with members of the House Intelligence Committee three days after the attack, also espoused the view that Benghazi was an out-of-control demonstration prompted by the YouTube video. According to the source, this was "shocking" to some members who were present and saw the same intelligence pointing toward a terrorist attack.