A credible and specific terrorist threat is being investigated in New York and Washington for the 10th anniversary of the Sept. 11 attacks. The investigation has not yet confirmed the threat that includes possible attacks on bridges or tunnels.
U.S. officials said Thursday they were investigating a detailed al-Qaida car bomb plot aimed at bridges or tunnels in New York City or Washington to coincide with the 10th anniversary of the Sept. 11 attacks, the first tip of an "active plot" targeting that date.
The Homeland Security Department said the threat is credible and specific, but unconfirmed. The nation's terror alert level has not changed, but it was under consideration Thursday night.
Security has been enhanced around the country in the weeks leading up to the 10th anniversary. Law enforcement officials have been wary, particularly after information gleaned from Osama bin Laden's compound in May indicated that al-Qaida had considered attacking the U.S. on the anniversary and other important dates.
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Law enforcement officials were investigating three people who recently entered the U.S. The threat came in late Wednesday night and is the first tip the U.S. intelligence community has received about an "active plot" targeting the anniversary, officials said.