The plane, which originated in Hawaii, landed safely at about 7 p.m. local time at the Seattle-Tacoma International Airport, where it was met by local law enforcement and FBI agents who interviewed the passenger in question, authorities said.

The security scare appeared to be a false alarm, and possibly a hoax, said Tom Simon, an FBI special agent in Honolulu, where the anonymous call was received.

"The passenger did not do anything wrong on the flight. It was a totally benign, normal, trans-Pacific flight," he said.

He said the passenger, identified by name by the individual who called the FBI, was cooperating with authorities. There were no immediate arrests.

"If he turns out to be a bad guy," the FBI in Seattle will pursue the case, Simon said. "If this turns out to be a prank phone call, the Honolulu FBI may choose to investigate that hoax phone call as a crime."

He said the anonymous call came at about the time the Alaska Airlines jet, Flight 819, was taking off from Kona airport on the Big Island of Hawaii en route to Seattle.

As a precaution, the North American Aerospace Defense Command (NORAD), a joint U.S.-Canadian operation, scrambled two F-15 fighters from the Oregon Air National Guard. The military jets encountered the Alaska Airlines plane just off the coast of Oregon over the Pacific, NORAD spokesman Al Blondin said.

The fighter jets stayed with the commercial airliner for the remainder of its flight, said Blondin, speaking from NORAD's headquarters in Colorado Springs, Colorado. (Reporting and writing by Steve Gorman; Editing by John Stonestreet)

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