WASHINGTON—A recent U.S. military raid on a terrorist group's hideout south of Baghdad, Iraq, netted intelligence that prompted New York City Mayor Michael Bloomberg to warn Thursday that the metropolis' sprawling subway system faced an explicit threat of terrorist attacks.
U.S intelligence and law enforcement officials in Washington, however, cautioned that the information that triggered Bloomberg's warning was shaky.
"The intelligence community believes that, although the information is specific, it is of doubtful credibility," said Russ Knocke, the spokesman for the Department of Homeland Security.
Knocke said U.S. experts were continuing to evaluate the information but had passed it on to New York and New Jersey officials early on out of an "abundance of caution."
New York City authorities appeared to be taking no chances and were deploying additional police and canine units around the subway system, which carries an estimated 4.5 million people every weekday and is the largest in the country.
Speaking at a hastily called news conference Thursday in New York, Bloomberg said the FBI had informed him about "a specific threat" against the system.
"We have never had before a specific threat to our subway system," he said. "This is the first time we have had a threat with this level of specificity."
U.S. intelligence officials said U.S. forces earlier in the week had raided a base belonging to Ansar al Islam, a small group linked to al-Qaida comprised of Islamic extremists from Iraq's Kurdish minority, in the city of Musayaf, south of Baghdad.
The raid recovered information that 19 suicide bombers using suitcases and baby carriages planned to hit the New York subway system, they said.
The information was passed to the FBI, which turned it over to New York officials.
Bloomberg said he'd waited several days to make the information public in order to give law enforcement officers time to derail any attacks.
New York City Police Chief Ray Kelly, appearing with Bloomberg, said the intelligence indicated that an attack could happen "in the coming days" and that police would be watching for and searching people with baby strollers, briefcases and backpacks.
The intelligence "was more specific to the target, it was more specific as to timing and some of the sources had more information that would lead one to believe that it was not the kind of thing that appears in the intelligence community every day," said Bloomberg.
But a federal law enforcement official and two U.S. intelligence officials warned that there'd been no confirmation of the intelligence.
It was unclear whether there was a specific plot or that the raid in Iraq had netted "a wish list" of targets, said the federal law enforcement official, who asked not to be identified by name because the information is classified.
The U.S. intelligence officials, who also declined to discuss the matter for attribution, said intelligence analysts were skeptical of the intelligence because the threats against the New York subway system had appeared for several days on a Muslim extremist Web site that's regularly monitored.
Al-Qaida and its allies normally don't broadcast their plans on the Internet, they said.
Moreover, they said, there's no evidence that Ansar al Islam—which translates into English as Partisans of Islam—have the means or expertise to carry out a major operation in New York City.
One of the U.S. intelligence officials said there was a concern that the Web site threat was intended to distract U.S. attention from al-Qaida's real plans, which he said were increasingly focused on driving American forces out of Iraq and igniting a civil war between Shiite and Sunni Muslims.
The U.S. intelligence officials said intelligence collected from a Baghdad apartment where a lieutenant to Abu Musab al-Zarqawi, al-Qaida's top man in Iraq, was killed in a shootout last week indicated that al-Qaida is focusing much of its attention and resources on creating a militant Islamic state in Iraq.
Similar indications were found in a recently recovered a 13-page, 6,300-word letter to al-Zarqawi from Osama bin Laden's top aide, Ayman al-Zawahiri, they said.
New York City has been on high alert for a terrorist strike since the Sept. 11, 2001, attacks.
Police have been randomly searching the backpacks and luggage of New York City subway riders since suicide bombers hit the London underground in July.
(c) 2005, Knight Ridder/Tribune Information Services.
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