U.S. officials said Thursday evening they have "specific, credible but unconfirmed" information about a threat against the United States coinciding with the 10th anniversary of the September 11 terrorist attacks. "We have received credible information very recently about a possible plot directed at the homeland that seems to be focused on New York and Washington, D.C.," a senior administration official told CNN Pentagon Correspondent Barbara Starr.
The official said the plot was believed to involve three individuals, including a U.S. citizen, who may have entered the United States. U.S. officials believed the threat was a vehicle laden with explosives, but "the intelligence picture is not completely formed," the official said. "Not enough is known about the potential operatives and their plotting."
Another source gave CNN conflicting information about possible details of the threat.
http://www.cnn.com/2011/US/09/08/terrorism.threat/index.html