Fresno, Calif. ? An ice-encased body discovered by two climbers on a Sierra Nevada glacier is believed to be that of an airman whose plane crashed in 1942.

The man was found wearing a World War II-era Army-issued parachute when his frozen head, shoulder and arm were spotted Sunday. An excavation is expected to take several days.

Park officials believe the serviceman may have been part of the crew of an AT-7 navigational training plane that crashed on Nov. 18, 1942. The wreckage and four bodies were found in 1947 by a climber.

Some 88,000 Americans are missing in action from past wars, military officers said. Most of them – 78,000 – are from World War II.