(CNN) -- It was one of the worst genocides since the Nazi era. The brutal Khmer Rouge took over Cambodia in 1975 and terrorized the population for four years, killing more than one million people. One of its infamous leaders died Thursday, escaping judgment for war crimes at the hands of a U.N. tribunal. Ieng Sary passed away in the capital Phnom Penh at age 87, the United Nations-backed court for Cambodia said. He was the foreign minister under, and the brother-in-law-of, Khmer Rouge dictator Pol Pot. On Tuesday, he was hospitalized for stomach pains. The Extraordinary Chambers in the Courts of Cambodia -- the U.N.-backed court -- will establish the cause of death before releasing his body to his family.
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He escapes justice for alleged genocide
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Genocide in Cambodia in the 1970's killed more than a million
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The defendants are all over age 77, and critics say the trial is dragging on
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People in Cambodia have shown high interest in the trial
For the next four years, the communist Khmer Rouge under @placeholder was blamed for the deaths of some 1.7 million people through torture, execution, hard labor and starvation.