Officials pursue al-Qaida bomb plot

WASHINGTON (AP) - U.S. officials said Thursday they were investigating a credible but unconfirmed threat that al-Qaida was planning to use a car bomb to target 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" around 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 raising it was under consideration Thursday night.

Law enforcement officials were investigating three people who recently entered the U.S. The threat was received by the U.S. intelligence community late Wednesday night, officials said.

"There is specific, credible but unconfirmed threat information," said Janice Fedarcyk, the assistant director in charge of the FBI's New York division. "As we always do before important dates like the anniversary of 9/11, we will undoubtedly get more reporting in the coming days."

The threat came in a single piece of information and was so specific - and came at such a time of already heightened alert - that it could not be ignored.