SAN FRANCISCO -- Air travelers who purchased the Clear Card to speed passage through airport security learned Monday night that financial troubles have brought the program to a sudden end.

The four-year-old Clear Registered Traveler program ceased operations at airports across the country Monday night.

Passengers paid as much as $199 dollars for the Clear Card, which was sold as a way to "fly through airport security" because the card holder had been pre-screened.

Business traveler Peggy Davis said she just renewed for a year and was shocked when she arrived at San Francisco Airport on Monday night and found the Clear Card checkpoint closed.

"Big shock. My flight's at 7:30, it's 6:30, so it could be tight, to see if I make it or not," said Davis. "This is totally unexpected."

A Clear employee who was shutting down the booth where customers enroll in the program said 50 to 60 Clear staffers at the San Francisco International Airport will lose their jobs.

The company Web site issued a statement that said Clear was unable to negotiate an agreement with its senior creditor and was ceasing operations as of 11 p.m. on June 22nd.

Clear was operating in 20 airports around the country, San Jose and Oakland among them, but further expansion never took off.

And with the recession reducing air travel, lines are shorter than they used to be.

Clear has yet to announce how it will handle its 165,000 members.