Phnom Penh Municipal Court on Thursday charged a 28-year-old man with making death threats against Prime Minister Hun Sen.
Court spokesman Suos Vithyearandy identified the suspect as Rom Chamroeun from Prey Veng province.
He is accused of using his uncle’s Facebook page to threaten to kill Mr Hun Sen and his family.
The threat was posted on the Facebook page of a user named Soeun Katkandal along with an image of two pistols.
It said: “Hun Sen I will kill you because if you aren’t killed Cambodia will never have peace. Me and my siblings will shoot Mr Hun Sen some day, and his wife and children.”
Chea Pov, anti-cybercrime director with the National Police, said a man named Krouch Soeun was initially arrested on Tuesday in Kratie province.
He was the owner of the Soeun Katkandal Facebook profile, but police found he could not read or write.
Mr Soeun told officers his nephew had created his Facebook page, which led to the arrest of Mr Chamroeun in Prey Veng province’s Por Reang district.
“We released the uncle because he was not involved with the offence,” Mr Pov said.
Mr Vithyearandy said the suspect had been detained in Pey Sar prison awaiting trial.
Earlier this week police arrested two women from Banteay Meanchey province and another man from Preah Sihanouk province on similar charges of threatening the life of Mr Hun Sen and his family.