NEW YORK (Bloomberg) — Continental Airlines Inc. and two regional carriers were fined $175,000 for stranding passengers all night on a grounded plane in August, the US Transportation Department said today.

Passengers were aboard a 50-seat jet operated by ExpressJet Holdings Inc. in Rochester, Minnesota, 90 miles south of Minneapolis, on a flight that had been diverted. Continental, which hired ExpressJet to make the flight, was fined $50,000. Both carriers are based in Houston.

ExpressJet was also fined $50,000 and Mesaba Airlines, a unit of Atlanta-based Delta Air Lines Inc., was fined $75,000 for its role in handling ground services for the flight.

"I hope that this sends a signal to the rest of the airline industry that we expect airlines to respect the rights of air travelers," Transportation Secretary Ray LaHood said in a statement announcing the fines.