A fourth former Khmer Rouge soldier has been arrested and charged for his role in the 1996 kidnapping and killing of British mine clearer Christopher Howes, a court official said last week.

Former Khmer Rouge fighter Sin Dorn was charged May 6 with premeditated murder over the deaths of Howes and his Cambodian translator, investigating judge Ke Sakhan told AFP.

Sin Dorn was also charged with illegal confinement of Howes and his translator and with being a member of rebel forces, he said.

Authorities arrested Sin Dorn on Friday in the remote northern outpost of Anlong Veng, the Khmer Rouge's final stronghold, he said.

"He has been placed in jail" pending trial, Ke Sakhan added.

In November, three other former communist rebels, including Khem Ngun, Loch Mao, and Cheap Chet, were arrested and received the same charges over the deaths of Howes and his translator, Huon Huot.

They left the Khmer Rouge after the movement disintegrated in 1998.

Khem Ngun, who served under the notorious Khmer Rouge commander Ta Mok, had joined the government and was awarded the rank of major general in the Cambodian military. The others became civil servants.

 All four men face life in prison if convicted, but no trial date has been set.

Khem Ngun allegedly ordered rebels under his control to shoot Howes and Huon Huot, a few days after they were seized near the famed Angkor Wat temples in northwest Cambodia.

At the time the communist Khmer Rouge was battling government troops in the final years of Cambodia's drawn-out civil war.

Howes, who was 37 at the time, was given the chance to leave his kidnapped team of 20 mine clearers from the Britain-based Mines Advisory Group to retrieve a ransom, but refused.

While the team was eventually released, Howes and Huon Huot were taken deeper into rebel-held territory and killed. His remains were found in 1998.

Families of the victims filed complaints in provincial court, but long delays forced the transfer of the cases to Phnom Penh.

Cambodia is littered with millions of landmines and other unexploded ordnance from nearly three decades of conflict which ended in 1998.