A terminal at Alaska's main airport was evacuated early Sunday after a passenger made reference to a bomb in luggage, officials said.

The terminal at Ted Stevens Anchorage International Airport was cleared as authorities searched through baggage, airport manager John Parrott said.

He said the incident began a little after midnight (1 a.m. PDT) when the man, who was traveling with two male companions, made a reference to a bomb in a bag that had been checked into luggage.

Travelers were evacuated to another terminal, while police and others search the luggage. Parrott said that so far, no explosive has turned up.

He said the three men were being interviewed by authorities. He declined to release any more information about them except to say that Anchorage was their point of departure. Parrott didn't have details on their destination.

"We don't know if this is a credible threat. That's what the interviews will help us determine," Parrott said.

The FBI and Transportation Security Administration are taking part in the investigation.

Meanwhile, aircraft have been landing but Parrott said no passengers have been allowed to board any aircraft.

"We are having passengers go to north terminal or the rental car area, providing shelter while waiting to resolve this," Parrott said.