Ho Sok, a secretary of state at the interior ministry, was arrested on Monday and later killed, a member of Hun Sen's party said.
Ho Sok was one of four senior Funcinpec members whom Hun Sen had accused of being responsible for two days of fighting in the Cambodian capital that left at least 58 people dead. Hun Sen, who ousted Prince Ranariddh on Sunday, said the four should be found and arrested.
Prince Ranariddh's top military adviser, General Nhiek Bun Chhay, was among the four identified by Hun Sen. Officials said the general was surrounded by troops loyal to the coup leader.
Away from Phnom Penh, fierce fighting shattered the silence around Cambodia's ancient Khmer capital last night, as rival forces clashed near the remote temple complex of Angkor Wat in the north-west.
And in another ominous sign, the authorities in neighbouring Thailand began evacuating foreign nationals, in scenes reminiscent of the panicked 1975 departure from the city when the Khmer Rouge took control. Phnom Penh's airport has remained closed to commercial traffic since heavy fighting reportedly damaged its facilities at the weekend. In Washington, the Pentagon ordered American warships to the region in case a full-scale evacuation of foreigners is necessary.
In Paris, where he is in self-imposed exile, Prince Ranariddh urged the world to condemn the coup. "I am asking the international community to take a clear position and to never recognise a government resulting from a coup d'etat," he said.
A joint statement by the Association of South East Asian Nations (Asean) has called for negotiations between the rival Cambodian factions. Cambodia is scheduled to join Asean later this month but the plans may now be delayed.
Cambodia's drift back to renewed warfare marks a failure for the United Nations peace effort in the country. Four years ago, democratic elections marked the end of a $2bn UN project to return Cambodia to peace after nearly 20 years of fighting. But the UN was unable to disarm the rival factions.
"Even if the 1991 peace deal could not be fully implemented, the situation would be much better now if they had tried to get the arms," said Kem Sokha, chairman of the Cambodian parliament's human rights commission.
Tanks and heavily armed troops were patrolling the streets of Phnom Penh last night. Hun Sen, who some see as a new dictator, voiced indignation at any suggestion of a return to the paralysis of a coali- tion government with Prince Ranariddh. He has accused his rival of forging a military alliance with the Khmer Rouge, under whose rule an estimated two million Cambodians died.Reuse content