Cambodian Prime Minister Hun Sen said Thursday he doubts whether summoning six of his colleagues to testify at the country's Khmer Rouge genocide tribunal will help the cause of justice, AP reported. The U.N.-assisted tribunal announced Wednesday that it was calling the country's current foreign minister, finance minister, national assembly president, senate president and two other senators to testify before the tribunal's investigating judge. All are top members of Hun Sen's Cambodian People's Party but also exercised some authority when the communist Khmer Rouge held power in 1975-79. Hun Sen himself once served as a Khmer Rouge officer and many of his main allies are former members of the group. The tribunal is seeking justice for the estimated 1.7 million people who died in Cambodia from execution, overwork, disease and malnutrition as a result of the group's radical policies. Hun Sen has repeatedly expressed his sharp dissatisfaction with any efforts by the tribunal to expand its scope and possibly include his political allies. The prime minister questioned the court's decision Thursday, saying his colleagues had already proven they were interested in seeing justice done. «They (the court) know that these people helped to topple the regime of (late Khmer Rouge leader) Pol Pot from power, and moreover, adopted the law to try the Khmer Rouge leaders as well,» Hun Sen said. He appeared to question why his colleagues would be called as witnesses at the request of the defense, saying their testimony would only increase their punishment. «Therefore how will justice be done?» he said. The tribunal is currently trying its first defendant, Kaing Guek Eav _ also known as Duch _ who commanded S-21 prison in Phnom Penh, where up to 16,000 people were tortured and then taken away to be killed. He is charged with crimes against humanity, war crimes, murder and torture. Also charged are Nuon Chea, the group's ideologist, Khieu Samphan, its former head of state, Ieng Sary, its foreign minister, and his wife Ieng Thirith, who was minister for social affairs.