International Business Times 
September 11, 2011
Two of the three people authorities are searching for after U.S. intelligence officials reported receiving a “credible” Sept. 11 anniversary terror attack might be American citizens, senior officials said Saturday.
While no evidence has been found that al-Qaida has sneaked in any terrorists, authorities kept a high alert as investigators search for proof of a possible plot planned to coincide with memorial events Sunday in New York and Washington, The Associated Press reported.
On Thursday, U.S. officials said they received intelligence that al-Qaida militants in Pakistan might be planning an attack and, because of the proximity to the Sept. 11 anniversary, officials are taking the threat very seriously.
As another indication of the severity of the threat, President Obama was briefed on the threat multiple times Thursday and directed U.S. intelligence officials to “take all necessary steps to ensure vigilance,” according to the White House.
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