U.S. raises terror alert level for rail systems

No specific warning signs
Chertoff said that U.S. authorities have “no specific credible evidence” pointing toward an attack in the United States. At the same time, he said, “we are also asking for increased vigilance” particularly in the U.S. transportation system.

He stressed that authorities are not asking Americans to avoid using their subways and bus systems in light of the worst attack in London since World War II. To the contrary, he said those who use mass transit should continue to do so.

Chertoff told reporters he was not aware of any specific evidence that had foretold the attacks in London. Dozens of rush-hour commuters were killed and hundreds injured when four blasts went off in the city’s subway system and a bus.

“I think our transit systems are safe,” Chertoff said, adding that there have been vast improvements in the nearly four years since terrorists struck the United States on Sept. 11, 2001.

The terror alert had not been raised in the United States since last August, when the Homeland Security Department increased it to orange — or high — for financial institutions in Washington, New York and Newark, N.J., in the run up to the November elections.

President Bush, in Scotland for a meeting of the Group of Eight leaders, conferred in a secure video conference with national security and homeland security officials in Washington.

“I instructed them to be in touch with local and state officials about the facts of what took place here and in London,” Bush told reporters from a summit of world leaders. Bush said he urged caution “as our folks start heading to work.”

Rice telephoned British Foreign Secretary Jack Straw offering assistance. She also visited the British Embassy in Washington to sign the condolence book.

“It may take some time to untangle this,” Rice said in an interview with the BBC. “But whoever did this, it’s a part of clearly a concerted campaign to try and terrorize innocent people and it’s certainly not going to succeed.”

Vulnerable trains
Subway systems are inviting targets for terrorists because they are difficult to secure.

The kind of screening equipment used to check passengers at airports can’t be used because it’s too slow for systems designed to quickly move large numbers of people.

“Mass transportation systems will always be vulnerable to some extent if we want to keep them as efficient as they are today,” said Rafi Ron, president of the Washington-based transportation security consulting firm, New Age Solutions.

About 29 million people take commuter trains, subways and buses daily in the United States, with the New York City area accounting for about a third of the total, said Alan Pisarski, a Washington-based national transportation policy analyst. The next-largest systems are Chicago, Washington, Boston and Philadelphia. San Francisco has the largest system on the West Coast.

James Carafano, a homeland security expert with the Heritage Foundation think tank, said trains are a tempting target for terrorists because they’re so predictable.

“It’s very, very easy to do reconnaissance,” Carafano said.

Despite the increase in the alert level for U.S. mass transit, security efforts were not being increased at airports, airline industry officials said.

“The Department of Homeland Security says they’re not raising the alert level for aviation,” said Ian Redhead, vice president of security for Airports Council International, a trade group representing airports.

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