Jailed Khmer Rouge leader Ieng Sary was released from Calmette hospital Friday, ending his second visit to the hospital in a week and raising concerns his health may be failing.

The return to the hospital of the ailing leader raises again the specter that the five jailed leaders will escape their days in court, even as the tribunal is preparing for the first trial since its 2006 inception, of Kaing Kek Iev, the chief of Tuol Sleng prison, early this year.

"His situation could be serious," Ang Oudom, Cambodian defense lawyer for Ieng Sary, said Thursday, adding that his client may need an operation. However, if the operation would cause adverse effects on his health, he said, "then the doctors would not do it."

Arrested in November 2007, Ieng Sary, 84, faces charges of war crimes and crimes against humanity for his role as the foreign minister of the Khmer Rouge regime. Of five jailed leaders, he has visited the hospital the most times.

He was released from Calmette Wednesday, Dec. 24, after two days in the hospital for treatment of a swollen leg, and readmitted Sunday, Dec. 28. Family members have told his lawyers he has kidney disease.