An outage that cut phone and data service in parts of California, Oregon and Washington caused wide-spread delays to Alaska Airlines flights on Monday as the carrier's reservations system was knocked off line.
Crystal Davis, a spokeswoman for Sprint Nextel, said the outages were caused by two cuts in the company's fiber optic cable network.
One was accidentally cut early Monday morning while maintenance work was being conducted on a rail track between Chicago and Milwaukee, she said.
The company is still investigating the cause of the second cut, which occurred between Tacoma, Washington and Portland, Oregon.
Davis said that fiber cuts are typically accidental, but that sabotage had not been ruled out as the cause of the second incident.
Alaska Airlines said on its Facebook page that it lost its connection to the Sabre reservations system, which it also uses to check customers in for flights.