Comrade Duch, the head of the Khmer Rouge and the person who ran Cambodia's notorious S-21 prison during the country's genocide, died on Wednesday, a spokesman for the tribunal that convicted him of war crimes in 2010 said.

Journalists witnessed his body taken to a local temple early Wednesday, where it was cremated. A doctor's letter confirming his death said he had died of "acute respiratory distress."

Duch, 77, whose given name was Kaing Guek Eav, was the first Khmer Rouge commander convicted of crimes against humanity, before being sentenced in 2012. He was arrested in 1999 while working at an aid agency under a false name.

During his testimony, he had pleaded for forgiveness, having taken to Christianity in his latter years. However, he shocked many in Cambodia when he sought to overturn his case during an appeal, saying he only "respectfully and strictly followed the orders."

Atrocities committed

A UN-backed tribunal rejected his suggestion that he was a junior official merely following orders. Duch was serving a life sentence at the time of his death.

As the first Khmer Rouge official to be tried, his testimony marked a major turning point for the millions of Cambodians who suffered under the brutal regime.

About 2 million people of Cambodia's 1970s population of eight million are believed to have been killed during the four-year rule of the Khmer Rouge regime. Of the more than 20,000 adult prisoners at the S-21 prison run by Duch, only seven survived.

Read more: Clearing Cambodia's leftover land mines: A dangerous job

The UN tribunal tasked with bringing the Khmer Rouge to justice continues to operate. However, it has effectively stalled over the cases of naval commander Meas Muth and alleged high-ranking member Yim Tith.

Farina So, principal deputy director of the Documentation Center of Cambodia, told DW that even if open cases remain, importance should be given to the efforts made to bring justice the millions of people who lost their lives.

"It is important that justice represents something meaningful to people, even if it's not complete," she said.

ls,jsi/sms (AFP, Reuters)