The Cambodia National Rescue Party issued a letter yesterday terminating the membership of overseas activist Yorng Noy, who also goes by Brady Young, for using social media to allege that Prime Minister Hun Sen’s eldest son Hun Manet was the son of a Vietnamese leader.

The letter, signed by the party’s acting president Kem Sokha, terminated his membership from the party’s US chapter in Long Beach, California, after he posted two videos last month – one by another source debating the rumours of Manet’s parentage, and another of himself commenting on the rumours and asking Manet to take a DNA test.

“This time let me be a spokesman for CPP supporters who have a question for Hun Sen and Hun Manet, but dare not ask it. So my question is – is Hun Manet Hun Sen’s son?” he says, speaking to the camera.

Party spokesman Yim Sovann said Noy’s actions were a violation of party bylaws, though he did not detail which bylaws had been broken and denied that the action was taken following an angry rebuttal by Hun Sen last week.

In those remarks, the prime minister lashed out at the rumours, adding that the opposition would need to “pay a high price” to make amends for such accusations.

Reacting to Noy’s termination, CPP spokesman Sok Eysan said the CNRP had demonstrated no will to clarify the matter without the strong reaction from Hun Sen.

Additional reporting by Ananth Baliga