NYC Increases Subway Security After Threat

Authorities stepped up security Thursday after receiving what city officials called a credible threat that the New York subway could be the target of a terrorist attack in coming days. But Homeland Security officials in Washington downplayed the threat, saying it was of "doubtful credibility."

Despite the differing takes on the seriousness of the threat, New York officials mobilized police officers to begin looking through commuters' bags, briefcases, baby strollers and luggage.

Mayor Michael Bloomberg called it the most specific terrorist threat officials had received to date. No one in New York had been arrested or detained, he said during a nationally televised news conference alongside Police Commissioner Raymond Kelly.

"We have never had before a specific threat to our subway system," Bloomberg said, adding that he still felt secure enough to take the subway home Thursday night. "Its importance was enhanced above the normal level by the detail that was available to us from intelligence sources."

A law enforcement official who spoke on condition of anonymity said the threat was "specific to place, time and method," which was a bombing. The official said the information resulted from the arrest of al-Qaida operatives in Iraq.

But in Washington, Homeland Security Department spokesman Russ Knocke said "the intelligence community has concluded this information to be of doubtful credibility. We shared this information early on with state and local authorities in New York." Knocke did not elaborate.

A counterterror official, who was briefed about the threat by Homeland Security authorities, said the intelligence was considered doubtful because it did not reflect "on-the-ground, detailed" information. Rather, the official, who also insisted on anonymity, said the intelligence was similar to "what can be found on the Internet and a map of New York City."

The law enforcement official in New York said that city officials had known about the threat at least since Monday, but held the information until two or three al-Qaida operatives were arrested in Iraq within the past 24 hours. Once the arrests were made, officials felt they could go public, said the official, who spoke on condition of anonymity because the investigation was ongoing.