In the wake of the terrorist attacks against London's rail and bus system, members of the U.S. Congress have been taking a closer look at preparedness in the United States for possible attacks on U.S. transit systems.

In a hearing Tuesday, a House of Representatives subcommittee dealing with emergency preparedness heard from officials from the metropolitan transportation systems in New York, Los Angeles and Washington, D.C.

Republican Congressman Peter King, who chairs the committee, noted what everyone already knows about the vulnerability of mass transit systems. "Because of the size and openness and the highly-networked character of mass transit there are no obvious checkpoints like those at airports to inspect passengers and parcels. Passengers are strangers, promising attackers anonymity and easy escape," he said.

Congressman Bill Pascrell, a Democrat from New Jersey, is among congressmen drawing attention to what they call the imbalance in attention paid to airline security since the September 2001 terrorist attacks, and strengthening mass transit securit.

"At home, these attacks provide a grim reminder of the terror that can easily be carried out on American rail systems. For anybody who has ever taken a train, this comes as no surprise," he said.

Congressman Pascrell says there must be greater cooperation between the federal government, and the Department of Homeland Security in particular, with urban mass transit systems to identify vulnerabilities and come up with counter-measures.

U.S. government officials testified about efforts to improve training and readiness for potential terrorism.

Robert Jamison, deputy administrator of the Federal Transit Administration, says information gleaned from the attacks in London and Madrid confirm that anti-terror technology alone is insufficient.

"Although opportunities to improve U.S. transit security still exist, we know that capital (money) expenditures alone are not enough to assure security. Perimeter fencing, securing yards, tunnels and bridges, and even extensive use of security cameras did not and would not have prevented either the London or Madrid attacks," he said.

He says U.S. officials continue to look back at the London and Madrid attacks to glean valuable information for authorities in U.S. cities.

Paul Lennon, director of intelligence and emergency preparedness management for the Los Angeles County Metropolitan Area Transit Authority, said "Training to respond to a terrorist attack is vital. In fact, to ensure a rapid and effective response in the event of a terrorist attack on one of our rail cars, our buses, or one of our hundreds of stations or facilities in Los Angeles county, training is not merely an option, it is mandatory."

As part of preparations for the potentially devastating occurrence of suicide bombings, Polly Hanson, chief of police in the Washington, D.C. METRO system describes some measures taken in the nation's capital:

"We have been working with local law enforcement, particularly the [U.S.] Capitol Police, in fact we're having a training session today. I think the Capitol Police went over to Israel and really looked at some of the dynamics over there. We had worked with them earlier, particularly when we started bringing long guns (powerful machine guns) into our system, to develop procedures, and we are reinforcing that now in light of London," he said.

Officials in Washington, D.C. are waiting to see the results of random searches being carried out in New York City, before deciding on similar measures.

"We started the random searches last week. The public seems to be very happy with it, they feel comfortable with what we are doing right now. NYPD (New York Police Department) is doing it throughout the New York City transit system and we are doing it on the commuter rails," said William Morange is head of security for the New York Metropolitan Transportation Authority:

In testimony on Capitol Hill this week, U.S. Homeland Security chief Michael Chertoff said the bombings in Madrid last year produced what he calls a stronger and more robust response on the question of rail security, with a focus on new technology to detect chemical and biological agents that might be used by terrorists.

At the same time, many lawmakers continue to draw attention to what they call the wide gap between billions of dollars spent for airline security and money directed to securing mass transit systems.