According to Pentagon figures, 2,491 Americans were missing in Indochina as of June 29 this year, including 42 civilians. Two are missing in action (MIA), the others are classified as ''killed in action, body unrecovered,'' or ''presumed killed in action.''
The majority of those missing are thought to have been lost in or over Vietnam and Laos. Others are missing in Kampuchea over the sea, or in China and in Thailand.
A breakdown by country is provided by the Joint Casualty Resolution Center in Hawaii. These figures show that of the 2,491 total, 1,394 are missing in Vietnam , 574 in Laos, 91 in Kampuchea, 4 in Thailand, 6 in China, and 422 are missing over the water.
Those missing in China are from aircraft that strayed into Chinese airspace and were shot down.
The proportion of war dead unaccounted for in the Vietnam war - around 4 percent - is much lower than those unaccounted for in either World War II or the Korean conflict (about 22 percent in both cases).
About a year after the end of both the Korean war and World War II, all those classified as missing were automatically recategorized as killed in action.