Hight blood pressure, exhaustion and dizziness forced Khmer Rouge tribunal investigating judges to stop questioning Nuon Chea Wednesday, his lawyer told VOA Khmer.

Son Arun said the judges halted a court interview after a morning of questioning, when Nuon Chea became dizzy.

His blood pressure was checked and found dangerously high, Son Arun said.

"They dared not to continue questioning him," Son Arun said of co-investigating judges You Bunleng and Marcel Lemonde. "So they let him rest."

Nuon Chea's answers from the session would be stricken from the record, "because my client could not speak properly," Son Arun said.

Nuon Chea had not slept well the night before questioning, and he was frustrated by the repetition of queries from the judges, Son Arun said.

When judges questioned him over the hierarchy of the Khmer Rouge, he could hear almost nothing, Son Arun told Agence France-Presse Wednesday, adding that the judges accused his client of being uncooperative.

After questions about the Khmer Rouge in the 1970s, Nuon Chea had difficulty answering, so Son Arun advised him to stop, the lawyer said.

"I told him not to answer if he could not answer," Son Arun said.

Seng Theary, executive director of Center for Social Development, welcomed the pursuit of the case, but said she wanted to know the details of health care given to Nuon Chea, to avoid suspicion he was being drugged.