ATA Airlines announced Thursday morning it is shutting down all operations and canceling all current and future flights.

More than 2,200 employees are out of a job. ATA also says it can no longer honor passenger reservations or tickets.

The airline shut down operations as of 3 a.m. Thursday morning. Customers who arrived for flights at Midway International Airport were turned away Thursday morning, while employees who showed up for work were told they were no longer needed.

The move comes after the airline filed for Chapter 11 bankruptcy on Wednesday in Indianapolis. In a statement posted on its Web site Thursday morning, the airline said it had become impossible to continue operations after the loss of a key contract for its military charter business.

- Customers of ATA Airlines are turning up at Chicago’s Midway Airport only to find the airline has discontinued all fights and filed for bankruptcy.

It appears that not only passengers are flabbergasted. Workers for the Indianapolis-based airline showed up for work, only to find out their services weren’t needed.

ATA says in a statement on its Web site that it became impossible to continue operations after it lost a key contract for its military charter business.

ATA announced last month that it would leave its hub at Midway Airport. The airline had flights from Midway to Dallas/Fort Worth and Oakland, California. It also had flights to Hawaii from Oakland, Los Angeles, Phoenix and Las Vegas.

All Current, Future Flights Canceled

The airline said in a statement that ATA customers should “seek alternative operations for current and future travel. They have composed a list of other airlines serving the same destinations as ATA.

TA said if passengers bought tickets using a credit card, they should contact their credit card company or travel agency to inquire about a refund for unused tickets. For tickets purchased with cash or check directly from ATA, refunds are not currently available, the airline said.

Cash or check customers may receive full or partial refunds by submitting a claim to the Chapter 11 proceedings for ATA, the airline said.

For more airline news, click here.