The former president of the Khmer Rouge has been arrested by armed Cambodian police, becoming the fifth member of the former regime to be brought before a United Nations-backed genocide tribunal.

Khieu Samphan was detained on Monday, days after he was admitted to hospital in the Cambodian capital, Phnom Penh.

At the time reports said he was being treated for a stroke.

Witnesses said the former Khmer Rouge leader was driven away in a police convoy shortly after he was discharged from hospital.

Officials at the tribunal confirmed the arrest, but gave no other immediate details.

War crimes charges

Khieu Samphan's detention had been widely expected, following the arrest last week of Ieng Sary, the Khmer Rouge's ex-foreign minister, and his wife Ieng Thirith, the regime's social affairs minister.

However, his illness and admission to hospital last week had cast doubts on whether he would be considered in a fit state to stand trial.

Ieng Sary and his wife were both charged with crimes against humanity, while Ieng Sary was also charged with war crimes.

The first trials under the much-delayed genocide tribunal are expected to begin next year.

Up to two million Cambodians are thought to have died through starvation, overwork or execution during the regime's 1975-79 rule.

Despite this, no senior member of the Khmer Rouge government has ever faced trial.

Pol Pot, the group's supreme leader and so-called "Brother Number One", died in his jungle hideout in 1998.

The former head of the Khmer Rouge's notorious Tuol Sleng torture and detention centre is due to appear before the tribunal to appeal against his detention on Tuesday.

Kaing Guek Eav, also known as Duch, was detained earlier this year on charges of war crimes and crimes against humanity.

His appearance will be the first public hearing for any former official of the Khmer Rouge.

PHOTO CAPTION

File photo shows former Khmer Rouge leader Khieu Samphan in the former Khmer Rouge stronghold of Pailin, near the Cambodian-Thai border. [Reuters]

Al-Jazeera