A mourning father yesterday called for a United Nations investigation into his son’s death in Oddar Meanchey police custody alongside a fellow inmate, which police contend was suicide.

Vy Pheakdey, 19, and Kong Kuyba, in his late 20s, were discovered dead in the Oddar Meanchey provincial police office. The bodies were swiftly moved from the scene to the provincial hospital, according to police and provincial Prosecutor Koy Kanya.

“They together hung themselves from an iron bar in the room,” Kanya said, adding they used an old krama and sarong left behind by cleaning staff. “I have examined them, and there are no beating injuries.”

Kuyba, an alleged drug dealer who had spent time in and out of jail, was arrested after his brother called the police because he had tried to burn down the family home.

Police then questioned Kuyba about a group of keys found in his possession, and he allegedly confessed to using them to steal valuable rosewood furniture from the home of a police official known as “Mr Vuth”. He named Pheakdey as his accomplice and said his brother, Tola, had sold the goods. Both were then arrested, the prosecutor said.

A policeman bringing them rice allegedly found the two men hanging. “I asked Tola [who was in the cell next door] and he did not hear any brawl or hitting,” Kanya said.

But Pheakdey’s father, Vorn Savy, 52, cast doubt on the official story, noting bruises on his son’s chest, back and waist. Pictures show deep red and purple patches on his back and at the nape of his neck. Savy said police only notified him of his son’s death the following day. “If my son died by hanging, why are there many bruises all over the body?” Savy said.

Kanya explained away the bruising by saying that the blood rushed to the back of the body when the corpse was laid out, and said the handcuffs had been removed while the men were in custody.

Dem Vandy, head of the provincial police’s minor crimes department, corroborated the official version of events and claimed Kuyba’s father was “happy” about his son’s passing. The deaths had spooked police, he added, saying a ceremony would be held at the site to ward off ghosts.

Srey Naren, provincial coordinator for rights group Adhoc, said such a case was unprecedented. “Savy suspected that his son might have been abused, so he wants to find justice,” Naren said.

He criticised the police’s lack of transparency, saying the family or human rights workers should have been allowed to scrutinise the scene before the bodies were taken away.

No matter their cause of death, Naren said, police should be held accountable for their “carelessness” in allowing the deaths to occur while the men were in their custody.

The UN’s Office of the High Commissioner of Human Rights representative Simon Walker said while OHCHR was aware of the case, it did not have full details.

However, he noted the UN Human Rights Committee had advised the Cambodian government in 2015 that it “should investigate allegations of use of lethal force by police and military, prosecute the perpetrators and provide compensation to the families”. Police gave Savy $50 to bury his son.

In Kandal province in late December, a mother filed a complaint demanding an investigation into her son’s death in prison by purported suicide, with authorities claiming the man jumped from a 1.2-metre high water tank to his death. The court and the Ministry of Interior’s General Department of Prisons promised to investigate the case.

Additional reporting by Erin Handley