WASHINGTON— The Bush administration is raising the terror alert to code orange for mass transit in the wake of London explosions, U.S. officials said Thursday.
Homeland Security Secretary Michael Chertoff planned to make the announcement at a press conference. The officials spoke on the condition of anonymity because the announcement had not yet been made.
The designation will apply to subway systems and light rail and select bus routes, officials said. he nation's overall terror alert will remain at yellow, or elevated.
At the same time, there was increased security at the U.S. Capitol.
Authorities moved to heighten security within several hours of the deadly attacks in London's transit system, although they said they had no intelligence indicating similar attacks were planned in the United States.
PoliceOne columnist Lt. Raymond E. Foster said the biggest domestic concern should be copycats because our public transportation isn't nearly as well protected as London's and even those not connected with Al Qaeda might say, 'gee, what a great idea.'
"Look at Europe, the entrance and exit from the Middle East is much (easier)," Foster said. "Here, you need to look at unattended packages as if they are real and focus yourself on your job, even the mundane tasks."
Foster said an additional risk to look out for is secondary devices, or devices that explode about 10 minutes after a primary device and are intended to injure first responders.
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."
U.S. officials were trying to determine, meanwhile, whether an Al Qaeda cell's claim of responsibility for the London attacks was credible. A U.S. official speaking on condition of anonymity because events were still unfolding said analysts were sifting through recent intelligence for evidence that other attacks might be in the works.
A senior U.S. counterterrorism official, speaking on condition of anonymity, said that because the attacks were well-coordinated and appeared fairly sophisticated, they were consistent with Al Qaeda's methodology.
Recent intelligence indicated that London was considered a prime target for Islamic extremists, in part because Al Qaeda was having difficulty getting people into the United States, the official said.
Security was stepped up in Washington, with bomb-sniffing dogs and armed police officers patrolling subways and buses. Police carrying rifles rode some trains, and passengers were being urged to report any suspicious activity. Security was also stepped up at the Pentagon.
A notice sent by the Capitol Police Department to top elected officials said that while there was "no intelligence regarding a specific threat" to the Capitol and the region but that security was being increased.
At the Pentagon, police officers said they had been placed on a heightened alert shortly after the London attacks.
Security around the massive home of the Defense Department, hit in the Sept. 11 attacks, was more visible than normal Thursday, with police officers in squad cars, on bicycles and on foot deployed in greater numbers than usual on the perimeter roadways and the Metro station.
Amtrak increased the number of police patrols and bomb-sniffing dog teams, and reminded railroad employees to be alert for suspicious activity, according to a company statement.
Additional reporting by PoliceOne News Editor Lindsay Gebhart
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