Women and children were intentionally blown up in underground bunkers. Elderly farmers were shot as they toiled in the fields. Prisoners were tortured and executed - their ears and scalps severed for souvenirs. One soldier kicked out the teeth of executed civilians for their gold fillings.

Two soldiers tried to stop the killings, but their pleas were ignored by commanders. The Army launched an investigation in 1971 that lasted 41/2 years - the longest-known war-crime investigation of the Vietnam conflict.

The case reached the highest levels of the Pentagon and the Nixon White House.

Investigators concluded that 18 soldiers committed war crimes ranging from murder and assault to dereliction of duty. But no one was charged.

Since the war ended, the American public has been fed a dose of movies fictionalizing the excesses of U.S. units in Vietnam, such as Apocalypse Now and Platoon. But in reality, most war-crime cases focused on a single event, like the My Lai massacre.

The Tiger Force case is different. The atrocities took place over seven months, leaving an untold number dead - possibly several hundred civilians, former soldiers and villagers now say.

One medic said he counted 120 unarmed villagers killed in one month.

For decades, the case has remained buried in the archives of the government - not even known to America's most recognized historians of the war.

Until now.