Kaing Khek Iev, the Khmer Rouge torture chief known as Duch, was officially charged for crimes against humanity Tuesday by the Khmer Rouge tribunal, which placed him in detention after a day of questioning.
Duch, 64, was the Khmer Rouge's lead interrogator at the S-21 Tuol Sleng torture center. Under his watch, as many as 16,000 Cambodians were tortured and executed, their bodies dumped at the Choeung Ek "killing fields" outside Phnom Penh.
He had long been expected to be the first defendant in a Khmer Rouge tribunal; he is the only cadre of the regime in custody.
The tribunal's investigating judges made the announcement late Tuesday.
Duch's charges come following the handing of a list of suspects from prosecutors to investigating judges. Four more unnamed suspects will be investigated before they are questioned.
Duch's detention by the Extraordinary Chambers in the Courts of Cambodia, or ECCC, the official name for the tribunal, moved him out of the custody of the military courts, where he has been since May 1999.
Brig. Gen. Ngin Sam An, the deputy military court chief who was the investigating judge while Duch was under military jurisdiction, said Duch was summoned for inquiry by the ECCC early Tuesday and did not return.
The military judge said his role in the prosecution of Duch will now come to an end.