WOODBURY - Law enforcement officials were out in full force today amid news of a terror threat just before the 10th anniversary of Sept. 11.

U.S. counterterrorism officials are chasing what's being called a specific and credible, but unconfirmed threat against New York City or Washington, D.C. They say the information, received Wednesday night, involves three people with a car bomb as a possible weapon on bridges or tunnels.

Authorities have increased patrols across the city, including near bridges, toll booths and trains. Officers are also pulling over cars and trucks, and conducting thorough searches. Police Commissioner Ray Kelly says many resources are being deployed.

Gov. Andrew Cuomo (D-N.Y.) also sent out hundreds of state troopers to help NYPD and MTA officers throughout the weekend. Meanwhile, Mayor Michael Bloomberg hopped on a subway this morning, telling New Yorkers that there is no need for alarm and that they should continue with their routines as planned.

Information gleaned from Osama bin Laden's compound in May had also suggested that al-Qaida was interested in attacking America on the upcoming anniversary.

President Barack Obama says he still plans to travel to Ground Zero this weekend.

Long Island steps up security amid terror threat Police give all clear in Hicksville after bomb squad investigationOfficials chase unconfirmed al-Qaida bomb plot