PHNOM PENH, Cambodia — Nuon Chea, the most senior surviving member of the Khmer Rouge, who was convicted of genocide and crimes against humanity and sentenced to life in prison, died on Sunday in Cambodia. He was 93.
His death at Khmer Soviet Friendship Hospital, where he had been transferred for medical treatment on July 2, was confirmed by the tribunal that convicted him.
To the end, he asserted in a statement to the court the correctness and even the heroism of his role in the Khmer Rouge, the radical Communist movement that caused the deaths of two million people from 1975 to 1979 through execution, starvation and overwork.
Known as Brother No. 2 — he was second in command to the movement’s founder, Pol Pot, who died in 1998 — Mr. Nuon Chea was convicted of, among other crimes, directing the forced evacuation of perhaps two million people from the capital, Phnom Penh, and overseeing the torture and killing of more than 14,000 people in a notorious prison, Tuol Sleng.
Often described as the movement’s chief ideologist, he was accused of laying out a “master plan” for the transformation of society that included the abolition of money and religion, the extermination of the educated class and the killing and expulsion of ethnic Vietnamese.
In the words of the court’s formal detention order, he planned or directed crimes including murder, torture, imprisonment, persecution, extermination, deportation, forcible transfer and enslavement.
He and Khieu Samphan, the nominal head of state for the Khmer Rouge, were the only senior leaders to answer in court for the crimes of the group. They were convicted of crimes against humanity and sentenced to life imprisonment in August 2014, and then in a separate trial of genocide, in November 2018.
Mr. Khieu Samphan remains in prison after his conviction.
The other senior defendants were Ieng Sary, the former Khmer Rouge foreign minister; and Mr. Ieng Sary’s wife, Ieng Thirith, the former minister of social affairs, both of whom died during the course of the trial. In a separate trial, the court reached its only other conviction, of Kaing Guek Eav, known as Duch, a prison commander who was subordinate to Mr. Nuon Chea and who was sentenced to life imprisonment.
The small number of convictions — along with mismanagement, infighting, corruption and political interference — drew criticism of the quality of the slow-moving trial, which at the time of Mr. Nuon Chea’s conviction had cost more than $300 million since beginning in 2006.
As a witness in his trial, Duch called Mr. Nuon Chea “the principal man for the killings” and said he had taken instructions from him “every three to five days.”
Among examples he gave in an interview with the journalist Nate Thayer before his arrest, Duch described an instance in which Mr. Nuon Chea had ordered the arrest of 300 Khmer Rouge soldiers as part of widespread purges.
“My prison was full,” Duch said. “He called to meet me and said, ‘Don’t bother to interrogate them — just kill them.’ And I did.”
In court — bald, frail and missing teeth — Mr. Nuon Chea slumped low in his seat, sheltering from the bright lights with a pair of large dark glasses. Guards helped him to and from his seat, as he first walked unsteadily, then as the years passed, using a wheelchair.
But of the four senior defendants, he was the most assertive and self-assured, describing his actions as a patriotic attempt to defend his country against aggression, particularly from Vietnam.
“Oppression and injustice compelled me to devote myself to fight for my country,” he said. “I had to leave my family behind to liberate my motherland from colonialism and aggression and oppression by thieves who wish to steal our land and wipe Cambodia off the face of the earth.”
His testimony amounted to a history lesson, through the eyes of the Khmer Rouge, of a country besieged by enemies, ravaged by American bombing and torn by subversives and traitors who needed to be rooted out through the evacuation of the cities and the purges in which the movement devoured itself.
Mr. Nuon Chea appeared to be more personally impactful than some other prominent figures in the movement, said David Chandler, a leading historian of Cambodia and the Khmer Rouge who is an emeritus professor of history at Monash University in Australia.
“He is a sincere, well-trained Marxist Leninist, and to some extent a Cambodian patriot, as well,” Mr. Chandler wrote in an email message before Mr. Nuon Chea’s death. “These facts tend to blur and mistakenly mitigate his record as the man more or less in command of the purges.”
Mr. Chandler added: “He was not a dreamer. Pol Pot was, and that appealed to people. Nuon Chea was not liked, because he couldn’t be reached or rented. He is genuinely impressive, as lots of Khmer are not.”
Mr. Nuon Chea was born Long Buntuoton on July 7, 1926, in Battambang Province of Cambodia. He studied law at the prestigious Thammasat University in Bangkok, where he became a member of the Communist Party of Thailand.
Back in Cambodia, he joined the Cambodian Communist Party and rose to become deputy secretary of its Central Committee and a member of its Standing Committee, the most senior bodies responsible for party policy, as well as chairman of the People’s Assembly. After the Vietnamese ousted the Khmer Rouge in 1979, he fled with other leaders into the jungles, where they continued a civil war until the final collapse of their movement in 1998.
In December of that year, Mr. Nuon Chea surrendered to the government, along with Mr. Khieu Samphan, and was treated by Prime Minister Hun Sen to a beach holiday and a visit to the ancient temples of Angkor.
Mr. Nuon Chea is survived by his wife, Ly Kim Seng; three daughters, Ly Bunthoeun, Lao Chea Linda and Nuon Chornita; and a son, Nuon Say.
At a news conference after his surrender, Mr. Nuon Chea offered a reluctant and peculiar apology, saying, “Actually, we are very sorry not only for the lives of the people of Cambodia, but even for the lives of all animals that suffered because of the war.”
Some Cambodians said this formulation might have reflected a Buddhist philosophy, although the Khmer Rouge banned religion and executed monks. But in the context of the extermination of as much as a quarter of the Cambodian population, it might have been said to have missed the point.
After his surrender, he was allowed to live a quiet life with his wife next door to Mr. Khieu Samphan, in the former Khmer Rouge stronghold of Pailin, until his arrest in September 2007.
Mr. Nuon Chea was an exacting inmate at the special holding center attached to the tribunal, demanding a more comfortable mattress, a diet of fish and vegetables and a Western-style toilet because, according to his lawyer, the usual squat toilet of Cambodia was hard on his knees.
His final statement in court, presented by his lawyer, Victor Koppe, called attention to his 500-page closing brief, including 4,000 footnotes, which the lawyer said presented the real history of the Khmer Rouge “and not some quote-unquote fake history.”
Mr. Nuon Chea denied involvement in the widespread killings. But in video recordings played to the court, he was heard acknowledging the purges, saying, “If we had shown mercy to these people, our nation would have been lost.”
He added: “We didn’t kill many. We only killed the bad people, not the good.”