Former S-21 prison guard Him Huy yesterday offered more details about the execution of children and high-value prisoners inside the compound as he was cross-examined by the defense teams for Khieu Samphan and Nuon Chea at the Khmer Rouge tribunal yesterday.

While Huy was vague about whether he was directly told about the executions or deduced that they were happening from conversations he had overheard, he was convinced that the southern end of the compound was used to kill children.

Several restricted buildings in the compound, he added, were used by high-level cadre Ta Ho and the prison’s commandant “Comrade Duch” – also known as Kaing Guek Eav, who was convicted in the tribunal’s Case 001 – to interrogate or eliminate important prisoners.

“Everyone said that [the children] were killed behind the prison,” Huy testified. He denied seeing the executions himself but said it was understood among guards that “usually the order to have children taken out meant that the children had to be killed”.

Huy said that Ta Ho and a cadre named “Peng”, who also had a leadership position at S-21, told him about interrogations and executions of high-value prisoners. However, at other times, he said that he “overheard” about the executions in conversations between Peng, Ho and others.

“I overheard that important people [were] to be killed behind prison, not killed outside, because the Angkar did not trust [drivers] who took people to different locations,” said Huy, using the name – meaning “the Organisation” – by which the Khmer Rouge often referred to itself.

He added that important prisoners were not sent to any other location except the buildings in the S-21 compound that were only accessible to Duch and Ho. On Wednesday, Huy testified that between 50 and 100 prisoners were executed at the S-21 site per week or fortnight, but “only after the prisoners gave the full confessions to the interrogators”.

Many low-value prisoners, including some mothers and minors, were transported to the area around Prey Sar prison, where they were put to work in the rice fields, said Huy.

He also described a time that he was told to drive prisoners to the killing fields but on the way to pick them up, the inattentive driver drove the vehicle into a ditch and had to tow it to mechanics for repairs. He never made it to the killing fields, Huy said.