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Frustrated lawmakers are calling on the Obama administration to get its story straight on what happened in last week's deadly attack on the U.S. Consulate in Libya, with President Obama coming under pressure to address the American people about the evolving narrative.

Secretary of State Hillary Clinton added her voice Friday to those calling the strike a terror attack. "What happened in Benghazi was a terrorist attack, and we will not rest until we have tracked down and brought to justice the terrorists who murdered four Americans," Clinton said.

The statement came after White House Press Secretary Jay Carney for the first time Thursday called the strike terrorism. Obama, though, continued to cite outrage over an anti-Islam film as a potential cause when asked about the attack during a voter forum hosted by Univision.

"There are going to be different circumstances in different countries. And so I don't want to speak to something until we have all the information. What we do know is that the natural protests that arose because of the outrage over the video were used as an excuse by extremists to see if they can also directly harm U.S. interests," he said. Obama originally referred to "acts of terror" in his initial statement on the attack last week but has since refrained from using the term or describing the attack as pre-planned.

"You hate to think that the president would purposely mislead the American people, but it sure looks like it to me," House Armed Services Committee Chairman Buck McKeon, R-Calif., told Fox News.

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McKeon was among several top-ranking lawmakers who expressed frustration following a briefing with administration officials late Thursday. Sen. John McCain, R-Ariz., said he learned "nothing" from it, claiming the administration is still blaming the anti-Islam film on YouTube for the attack that killed four Americans including the U.S. ambassador.

"It's not the video. It's the Islamists who are pushing this video," McCain said.

He and other lawmakers claim the attack was clearly pre-planned and could lead back to Al Qaeda or an affiliate. Obama, in his interview with Univision, did not say whether Al Qaeda might be involved, saying the matter is still under investigation.

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McKeon told Fox News that it's time for Obama to address the American people about what's happening.

"If he'd spend some time in Washington ... rather than traveling around ... to raise money and campaign for four more years of what -- yeah, I think it would be good if he did a little bit of what he's being paid to do," he said.

Several concerns have been raised about the version of events being pushed by administration officials.

Foremost, U.S. Ambassador to the United Nations Susan Rice's claims that the attack was a "spontaneous" event triggered by protests in Cairo were challenged by claims out of Libya and intelligence sources that the strike was premeditated and possibly tied to a former Guantanamo inmate. Sources also said there was no major protest in Benghazi before the strike, which further challenged assertions that the strike was part of a demonstration spun out of control.

Furthermore, Fox News has confirmed that the two former Navy SEALs killed in the attack were not working security for the State Department but were in Benghazi for a separate agency. And they were not initially at the consulate -- but a separate facility -- when the main building came under fire last Tuesday night.

These details also appear to conflict with the account given by Rice on ABC's "This Week."

She said: "We had a substantial security presence with our personnel. ... Tragically, two of the four Americans who were killed were there providing security. That was their function. And indeed, there were many other colleagues who were doing the same with them."

Some lawmakers have called for an independent investigation, expressing concern about whether the administration is handling it appropriately.

Following Thursday's briefing with Secretary of State Hillary Clinton and others, Sen. Bob Corker, R-Tenn., reportedly slammed the meeting as "the most useless, worthless briefing that I have attended in a long time."

"It was like a one-hour filibuster with absolutely not one single bit of new information being brought forth," he said, according to Foreign Policy magazine. The briefing "if anything, built far greater distrust about what's happening than just answering questions. It was pretty unbelievable."