Hun Manet speaks in a press conference at Phnom Penh international airport, after his visit in the United States. (Hean Socheata/VOA)
Hun Manet speaks in a press conference at Phnom Penh international airport, after his visit in the United States. (Hean Socheata/VOA)

A U.S. federal court is due to open proceedings Thursday against the eldest son of Cambodian Prime Minister Hun Sen. The case is tied to Cambodian opposition party spokesman Meach Sovannara, who has alleged wrongful imprisonment. The opposition activist also holds U.S. citizenship.

A complaint filed in April alleges Lieutenant General Hun Manet and Cambodian government officials are guilty of crimes against humanity, including torture, illegal detention, terrorism and illegal imprisonment.

Judge George H. Wu of the Central District Court of California will hear a second defense motion to dismiss the case, while the plaintiff's lawyers will argue that it should move to trial.

In April, as Hun Manet toured parts of the United States that are home to large Cambodian diaspora communities, he was greeted by Cambodian-Americans protesting Phnom Penh's human rights violations and domestic property seizures.

A large crowd of Cambodian Americans protests agai
FILE - A crowd of Cambodian Americans protests the visit of Lt. Gen. Hun Manet in Long Beach, California, April 9, 2016.

On the last day of Hun Manet's visit, he was served with court documents by American private investigator Paul Hayes, who was hospitalized after allegedly being thrown to the ground by one of the general's bodyguards outside a restaurant in Long Beach, California.

Hayes' subpoena was tied to the wrongful imprisonment lawsuit brought in court by Meach Sovannara.

Meach Sovannara is currently serving a 20-year sentence for taking part in a protest in Phnom Penh in late 2014; he is one of 11 activists jailed on insurrection charges for clashing with police over the closure of a protest site in the capital.

"My husband has suffered some mental difficulties and has been sick a lot," his wife, Jamie Meach, told VOA's Khmer service.

Hun Manet said in a statement to the court that he would not be in the United States while the case is being heard. He has denied being served papers on the day in question, claiming tight security and protests outside the restaurant caused him to be accidentally pepper-sprayed.

"At no time on April 9 was I aware there was a man approaching me to hand me any legal papers," he said.

According to California's guidelines on civil procedures before trial, Hayes' attempt to bring the subpoena to Hun Manet's attention were sufficient to qualify as having served the documents.

This report was produced in collaboration with VOA's Khmer Service.