Detained Khmer Rouge ideologue Nuon Chea was sent to the hospital for a third time Friday following his detention just one month ago.
He was examined by French doctors at Phnom Penh's Calmette hospital in a routine check-up, tribunal spokesman Reach Sambath said.
"He has to live a long time, so he can defend himself and face the law," he said. "So we have to pay serious attention to him."
The health of Nuon Chea and other surviving leaders of the Khmer Rouge is of concern to those who fear they may die without seeing a day in court. Nuon Chea was arrested and charged with atrocity crimes Sept. 19.
High blood pressure, exhaustion and dizziness forced tribunal investigating judges to stop questioning him last month, and he has complained in the past of pain in his shoulders and feet and "the illness of age."