The announcement came as Mineta and the White House scrambled to close gaps between Republicans and Democrats on Capitol Hill over aviation security legislation that would transfer control of screening operations to the federal government.
"The president is working on it," Mineta said before a critical White House meeting later in the day with President George W. Bush and key congressional players in the fierce debate over whether to make airport screeners federal workers.
Mineta said that despite the implementation of increased aviation security since the Sept. 11 hijack attacks there were inconsistencies that had seen a gun get through the screening process at New Orleans airport last week.
"This is intolerable," Mineta told state and local government transportation officials after meeting with Federal Aviation Administration inspectors earlier in the day.
He also has asked the Transportation Department's inspector general's office to provide special agents to supplement the FAA's 500 airport inspectors.
Mineta said an unacceptable number of deficiencies continued to occur, undercutting efforts to tighten aviation security and hurting consumer confidence in air travel.
"When we find ineffective or inadequate implementation of security measures we must crack down on those failures," Mineta said. He said agents would rescreen passengers and close airport gates or concourses to enforce security, if necessary, even if it delayed flights.
"We're going to go to zero tolerance," Mineta told reporters after his speech and one day after the Justice Department warned of possible new attacks in the United States or against its interests overseas.
Experts agree with Mineta's initiative and say specific procedures need to be added to the airport security regimen, reports CBS News Correspondent Sandra Hughes.
"Far too few bags are being checked for explosive devices or screened in any other way...to find the presence of other contraband items," said Gerald Kauvar an airport security expert with the research group RAND.
In 1996, following the bombing of PAN AM flight 103 over Lockerbie, Scotland, a White House security commission recommended that all checked bags should be screened for explosives but airlines balked at the idea, saying it couldn't be done without causing unacceptably long delays.
Though all carry-on bags are x-rayed, only about five percent of checked luggage is scanned for explosives.
The Department of Transportation recently found that bomb detection machines are being used at only 10 percent of capacity.
And on domestic flights, bags are not matched to passengers -- meaning a person could check a bag and never board the fligt.
Some flight attendants say this causes them constant fear. According to Patricia Friend of the Association of Flight Attendants, "they believe they are taking a risk every time they go to work and that is an unacceptable feeling."
A senior Transportation Department official said Mineta wants to change the "posture and tempo" of screening oversight without legislation mandating fundamental changes.
"We want to send a clear message to contractors that we're not going to have business as usual," the official said.
He said Mineta was angry at an incident last week when a passenger carried a loaded handgun gun aboard a Southwest Airlines Boeing 737 in New Orleans. The man gave the weapon to a flight attendant and was not charged with a crime.
Mineta also was unhappy with developments this month involving the nation's largest baggage and passenger screening firm, Atlanta-based Argenbright Holdings, which settled new allegations in Philadelphia about employee background checks.
From coast to coast, security scares are raising anxiety over the safety of flying.
A written bomb threat on board a New York to Dallas flight forced it into an emergency landing at Washington's Dulles Airport Monday. The United Airlines terminal at San Francisco's airport was recently closed after an abandoned bag appeared to have explosives inside. Both incidents were false alarms.
Mineta urged Congress to pass aviation security legislation, calling for support of a bill being offered by Republicans in the U.S. House of Representatives that would have federal employees supervise private screeners.
The Senate has already passed an aviation security bill that would make all airport screeners government employees but House Republicans have objected to a massive increase of the federal payroll.
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