Alert in New York over subway terror warning

The city has been put on "orange" alert which is second highest in the colour-coded system developed by the United States Department of Homeland Security and commuters have been advised against bringing backpacks, heavy packages and baby strollers as far as possible in the subway stations, officials said.

Announcing the enhanced security measures Thursday, Mayor Michael Bloomberg said officials had received information from Federal Bureau of Investigation about a "specific threat." But he said officials do not believe that any of the plotters are in the city now.

According to authorities, this is first time they have received specific threat against attacks on the subway system and their information shows that baby strollers packed with explosives could be used in the attack.

Commuters are taking the threat seriously in view of earlier terrorist attacks in London underground trains and in Spain. Searching of packages carried by commuters was stepped up. Visibility of uniformed police and number of undercover agents has also been increased to reassure the travellers.

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But in Washington, some officials of the Homeland Security Department sought to downplay the threat, saying that it was "specific yet non-credible" and anti-terror officials were unable to verity details.

There are indications that a terrorist attack on New York's subway system is possible "in coming days", Police Commissioner Raymond Kelly said. But he declined to give details, citing security concerns.

Quoting an unidentified "well-placed" source, CNN said the same intelligence also led to a raid against suspected al Qaeda operatives in Iraq. It quoted a FBI official as saying that there is possibility that this particular threat "may be resolved in the coming days."

In a televised press conference, Bloomberg television said no one has been arrested or detained in New York but the threat is specific to date.

However, to reassure the commuters, he said he still felt safe enough to take the subway home Thursday and to office on Friday. "Its importance was enhanced above the normal level by the detail that was available to us from intelligence sources," he added.