A Cambodian court found four former Khmer Rouge guerillas guilty of the 1996 kidnapping and murder of a British deminer and his Cambodian translator and sentenced them to 10 to 20 years in prison.

Judge Iv Kim Sri acquitted a fifth man because of a lack of evidence.

Briton Christopher Howes, his translator Huon Hourth and about 30 other people were abducted by Khmer Rouge guerillas during a demining mission in Siem Reap, about 300 kilometres north-west of Phnom Penh and home to the Angkor Wat temple complex.

The court heard that Howes, 37, had acted heroically, negotiating the release of all but himself and Hourth before the pair were marched to the rebel stronghold of Anlong Veng, 125 kilometres north of Siem Reap and home to Khmer Rouge military commander Ta Mok and the movement's leader Pol Pot.

They were shot and their bodies burned, the court heard.