Nonetheless, the FBI wants law enforcement to remain on high alert and guard against possible terrorist activities in the United States and abroad, officials said.
Last Thursday, California Gov. Gray Davis announced that federal officials have "credible evidence" that terrorists may be targeting California bridges. He cited San Francisco's Golden Gate and Bay Bridges, the Vincent Thomas Bridge at the Port of Los Angeles and San Diego's Coronado Bridge as possible targets for attacks Nov. 2 - 9.
His decision to reveal the potential threats had the support of federal officials, although they didn't make the information public until after he spoke out.
The Justice Department later confirmed that it had warned officials in eight Western states about possible attacks on bridges. However, Attorney General John Ashcroft said the warning had only "relative credibility."
The alert was sent to law enforcement agencies in California, Washington, Oregon, Arizona, Nevada, Utah, Montana and Idaho. "Reportedly, unspecified groups are targeting suspension bridges on the West Coast," the FBI message said.
CBS News Correspondent Jim Stewart reports the decision to alert the states was based on an intelligence assessment made by the U.S. Customs Service, and was apparently based on a single source.
Officials expressed concern about the reliability of that source, but felt that in today's climate they had no choice but to pass it along.
Homeland Security Director Tom Ridge said the advisory was not intended to be made public. "I respect the decision Governor Davis made; he exercised his judgment," said Ridge. "Had he chosen not to reveal, I would have respected that as well."
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