The Khmer Rouge's 76-year-old former head of state, who is awaiting trial on war crimes charges, has suffered an apparent stroke and can barely speak, his lawyer said Wednesday.

Khieu Samphan, a former Khmer Rouge head of state shown here in April, is believed to have suffered from a stroke. (Heng Sinith/Associated Press)

Khieu Samphan was rushed from his detention cell to a hospital on May 21 with high blood pressure. Since then, his condition has worsened, said attorney Say Bory, who is defending him at the UN-backed genocide tribunal scheduled to start later this year.

The lawyer said he believed Khieu Samphan had suffered his second stroke following one in November, though doctors have not issued a diagnosis.

"The left side of his body is nearly deadened," Say Bory told the Associated Press.

The tribunal's spokesmen and Khieu Samphan's doctors could not immediately be reached for comment.

The long-delayed tribunal is seeking justice for atrocities committed by the Khmer Rouge when it ruled Cambodia from 1975-79.

The regime is blamed for the deaths of 1.7 million people who died of starvation, disease, overwork and execution.

Khieu Samphan is among five suspects facing trial for their alleged roles in the regime's brutality. He faces charges of crimes against humanity and war crimes.

All five defendants are aging and infirm. Many fear the aging suspects might die before they ever see a courtroom.