Washington (CNN) -- President Obama will award the Medal of Honor, the military's highest award for bravery, to Air Force Chief Master Sgt. Richard Etchberger for his valor in saving the lives of three wounded comrades at a then-secret base in Laos in 1968, the White House announced Friday. After Etchberger saved his fellow airmen, he was shot and killed by enemy fighters. His heroics were kept a secret for years because the United States wasn't supposed to have troops in Laos during the Vietnam War. President Lyndon Johnson rejected a nomination for Etchberger to receive the Medal of Honor at the time because of the political trouble it could have stirred up.
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NEW: The United States did not want to admit it had troops in nominally neutral Laos
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Chief Master Sgt. Richard Etchberger's heroism was hidden for years
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He died after saving three comrades in Laos
According the @placeholder, Etchberger deliberately exposed himself to enemy fire "in order to place his three surviving wounded comrades in the rescue slings permitting them to be airlifted to safety."