The House on Thursday passed a broad package of measures designed to improve airline security but narrowly rejected a full federal takeover of security screening at the nation's airports.

The action puts the House in conflict with a unanimous Senate vote to place responsibility for screening passengers and baggage with a new 28,000-member federal security force working under the U.S. Department of Justice. Instead, the House would allow private security firms to perform screening under federal supervision.

In the crucial vote on security screeners, Illinois Reps. Rod Blagojevich and Luis Gutierrez of Chicago were among six Democrats who joined Republicans to defeat the Senate version of the legislation 218-214. Eight Republicans supported the Senate version.

Shortly afterward, the House voted 286-139 to approve the sweeping package of aviation security measures, many of which closely resemble provisions in the legislation approved by the Senate in response to the Sept. 11 terrorist attacks.

Both versions would require strengthened cockpit doors, place more armed sky marshals aboard airplanes and allow pilots to carry guns as a last-ditch defense against cockpit intruders. Both also would require that all airport security screeners be U.S. citizens and would mandate criminal background checks on airport employees allowed access to tarmacs and other secure areas.

Negotiators from the two chambers will have to resolve differences in the versions, including the dispute over security screeners, a contentious ideological issue that already has delayed the security legislation for weeks.

With the nation on high alert for another terrorist attack and a peak travel period surrounding Thanksgiving less than three weeks away, leaders of both political parties pledged this week to work to resolve their differences as quickly as possible.

Bush welcomes vote

President Bush welcomed the House vote and asked congressional leaders to stick to their word.

"The American people deserve tough security standards, and the House plan delivers. I urge the House and Senate to quickly work together to send a strong and effective bill to my desk," Bush said in a statement issued by the White House.

The competing visions for the security force spurred frantic lobbying throughout the week, with representatives of private security firms fanning out across Capitol Hill and Bush summoning wavering lawmakers to the White House to make the case against a federal workforce.

Moderate Rep. Jack Quinn (R-N.Y.) said Transportation Secretary Norman Mineta spent an hour lobbying him in person, and the president phoned to make a final plea for his support on Thursday.

Conservatives say turning over airport security to federal employees would be a dramatic and unwarranted expansion of government. They also said it would be easier to fire poorly performing screeners if they worked for a private security firm rather than directly for the federal government.

In debate, House Majority Leader Dick Armey (R-Texas) invoked the wartime prestige of the presidency to rally support.

"Put your confidence in the president. Give the president the ability, the authority to do what is necessary to keep our children safe in the air," he said.

Democrats say the terrorist attacks transformed airport security screening into a crucial law-enforcement function that should not be delegated to private companies.

"I ask all of you: Do you want to contract out the Capitol Police? Do you want to contract out the U.S. Marines? Do you want to contract out the FBI and the Customs Service? I don't think so," said Minority Leader Richard Gephardt (D-Mo.).

Current system draws criticism

Both Republicans and Democrats were critical of the current system for screening passengers, which leaves responsibility with airlines. In most cases, the airlines hire private security contractors.