Cambodian rebellion during the Vietnam war, if my memory does serve me correctly.
I think they were the Cambodians that the communists supported, and so the Vietnamese army was sent into cambodia to sweep it, since maericans were not allowed in cambodia. it was a major disaster, and the south vetnamese army had to retreat.
i cannot think of the campaign name though, they were numbers, i think 714, 517, something like that.