Protesters destroy an American flag pulled down from the U.S. embassy in Cairo, Egypt, Tuesday, Sept. 11.
A White House spokesman today said it is apparent that last week's attack in Libya that killed a U.S. ambassador and three other Americans was an act of terrorism.
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"It is self-evident that what happened in Benghazi was a terrorist attack," said White House spokesman Jay Carney."Our embassy was attacked violently and the result was four deaths of American officials."
Carney spoke as CNN and others, citing unnamed sources, reported that slain U.S. ambassador Chris Stevens had "worried about what he called the never-ending security threats in Benghazi and mentioned his name was on an al Qaeda hit list."
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As U.S. officials continue to investigate the deaths of Stevens and three other Americans, National Counterterrorism Center director Matthew Olsen told a Senate hearing: "I would say, yes, they were killed in course of terrorist attack on our embassy."
U.S. officials initially attributed the death to protests over an anti-Islam that got out of control.
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Aides to President Obama said the attack remains under investigation, including the state of security at the U.S. consulate in Benghazi, Libya.
President Obama "is concerned that violent actions were taken that led to the deaths of four Americans," said White House spokesman Jay Carney.
"He is absolutely concerned that we take the necessary measures to make sure that those who killed Americans are brought to justice," Carney said. "And he has been focused from the beginning on ensuring that adequate security reinforcements be brought to bear at embassies and consulates and diplomatic facilities where that's deemed necessary."