Homeland Security urges Americans to be vigilant this weekend [Updated]

In the face of what counterterrorism officials called a “credible but unconfirmed terror threat involving New York or Washington,” the Department of Homeland Security is calling on Americans to be vigilant this weekend as the anniversary of 9/11 looms.

The threat was reported Thursday by Fox News and later by the Associated Press.

New York City Mayor Michael Bloomberg and Police Commissioner Raymond Kelly are expected to give a news conference about 6:30 p.m. PT to talk about the threat, NBC News reported.

The Wall Street Journal reported Thursday that “al Qaeda militants in Pakistan may be preparing to carry out car bombings.”

Few details were available as the afternoon waned on the West Coast, but a DHS statement said, in part, “As we know from the intelligence gathered from the OBL [Osama bin Laden] raid, AQ [Al Qaeda] has shown an interest in important dates and anniversaries, such as 9/11. In this instance, it’s accurate that there is specific, credible but unconfirmed threat information.”

The statement also noted, “We take all threat reporting seriously, and we have taken, and will continue to take all steps necessary to mitigate any threats that arise. We continue to ask the American people to remain vigilant as we head into the weekend.”

So far, no information has been released on what, if any, procedural changes might be implemented at airports, train stations or cruise ship ports.