Strengthening of security against further terrorist attacks was a major topic Wednesday for members of the U.S. Congress. In hearings, lawmakers pressed government officials on progress in airport and rail security, just as new questions were being raised about security at one of the nation's busiest airports.

A recent published report saying thousands of bags were being loaded on passenger aircraft at Newark International Airport without being scanned for explosives was one subject of a congressional hearing on Capitol Hill.

The Newark, New Jersey Star Ledger newspaper quoted unidentified security personnel complaining about a shortage of qualified screeners at the airport.

New Jersey Governor James McGreevey seized on the report to criticize the Transportation Security Administration (TSA), established by Congress in the wake of the September 11, 2001 terrorist attacks.

At Wednesday's hearing of a House Homeland Security subcommittee, TSA official Steven McHale defended the agency.

"We have significantly increased the staffing at Newark in the last few weeks, and I believe that the statements in that article are grossly out-of-date," he said.

But several lawmakers expressed impatience with the agency. In questioning Mr. McHale, New Jersey Democratic Congressman Bill Pascrell said the government needs to be more open with the public about security weaknesses at major airports.

"Why are you reluctant to tell the public what percentage even of baggage is not checked at Newark Airport? The public uses that airport every day," said Bill Pascrell.

Newark International was one of three airports from which al-Qaida terrorists hijacked passenger aircraft to use in the terrorist attacks of September 11, 2001.

Outside the building where the hearing was taking place, members of the largest union representing flight attendants demanded that Congress require airlines to provide counter-terrorism training.

Patricia Friend is president of the Association of Flight Attendants.

"The flight attendants in this country are united completely behind the issue of demanding that we get the proper training that we need to face the security threats of the 21st century," she said.

Flight attendants, supported by some key House and Senate Democrats, accuse Republicans of giving in to pressure from airlines to make such training optional rather than mandatory.

Democratic Senator Joe Lieberman and Massachusetts Congressman Ed Markey both recalled September 11, 2001 terror attacks in urging a change.

LIEBERMAN: "Two-and-a-half years ago, four planes were hijacked, and used as deadly weapons against innocent Americans. Two-and-half years later, flight attendants still have not been trained to defend your passengers and yourselves from a similar God-forbid hijacking attempt in the future."

MARKEY: "The TSA continues to tell us that commercial airliners remain at the top of the terrorist target list. But you are still not receiving meaningful counter-terrorism training."

Legislation in the House and Senate would require mandatory, comprehensive counter-terrorist and self-defense training for all airline attendants.

Alice Hoglan, whose son Mark Bingham, was among passengers and flight attendants who resisted hijackers of Flight 93, was among those at Wednesday's demonstration.

"It is unconscionable that the decision about who should be trained, and to what extent they should be trained, should be left [in] the hands of the airlines," said Alice Hoglan. "We have seen what decisions left in the hands of the airlines have done in the past. We cannot allow that."

As the summer travel season approaches, and Congress works on legislation authorizing government spending, members are elevating the visibility of transportation security issues.

In other developments, a House committee Wednesday approved and passed on for consideration by the full House of Representatives legislation to begin steps to equip passenger aircraft with defenses against shoulder-fired missiles.

And in the wake of hearings that revealed weaknesses in railroad security, lawmakers are also seeking to increase the amount of money to be spent on enhancing rail security.