More Trouble For Airport Security Co.

When Argenbright screeners lost track of a San Francisco passenger with possible traces of explosives on his shoes, the nation's largest airport security contractor may have also lost its last chance.

The Department of Transportation now has "blacklisted" Argenbright and is moving immediately to replace the security company with competitors at dozens of U.S. airports, CBS News Correspondent Bob Orr reports.

In a statement, Argenbright called the DOT's action "unnecessary," but promised to "cooperate and minimize disruption to airlines and their customers."

But there's a troubling security Catch 22.

The government apparently is stuck with the company at three major airports: Denver International, Orlando and Washington Dulles.

At all three, Argenbright is the only security provider. Since it could take months to train and hire replacement federal screeners, Argenbright workers will remain on the job.

"These are three critical airports," says David Stempler of the Air Travelers Association. "Dulles serves the nation's capital, Orlando a key leisure spot, Denver for the Olympics and skiing. It's just outrageous we have to rely on this incompetent company."

Argenbright has been involved in numerous security lapses. The company was fined more than $1 million for hiring convicted felons at Philadelphia International airport. And last November, after the terrorist attacks, Argenbright screeners allowed a Chicago passenger to carry seven knives, mace and a stun gun past a security checkpoint.

Now Argenbright also has trouble at the U.S. State Department. Sources tell CBS News the company allegedly made false statements in applying for security contracts at the U.S. Embassy in Athens and at the U.S. consulate in Hong Kong – charges Argenbright denies.

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