Fire broke out Thursday aboard a North Sea oil rig with 67 men aboard, forcing a massive helicopter rescue in which all but one of the workers was picked up, the Royal Air Force said.

An RAF spokesman said all of the rescued men were lifted off the Ocean Odyssey - operated by the British arm of the American Arco oil company - by helicopters and ferried to safety in two nearby support ships."We understand that 66 people of 67 on the rig have been rescued," the spokesman said. "One person is unaccounted for."

The Ocean Odyssey, a semi-submersible drilling rig, is located 138 miles east of Aberdeen, police said. The location is 80 miles south of the remains of the Piper Alpha platform that exploded July 6, killing 167 men, local oilmen said.