Malaysian police have sought DNA samples from a family member related to Kim Jong-nam, the murdered step brother of North Korean leader Kim Jong-un, to release his body. Officials have made it clear that his body will not be transferred from Malaysia until a credible connection is established.

The police said that they have received an official request from Pyongyang seeking custody of Jong-nam's body, which they would agree to only after medical and diplomatic procedures are completed.

"So far, no family member or next-of-kin has come to identify or claim the body. We need a DNA sample of a family member to match the profile of the dead person," Selangor police chief Abdul Samah told AFP. "North Korea has submitted a request to claim the body, but before we release the body we have to identify who the body belongs to."

Officials in Kuala Lumpur had earlier confirmed the body of the estranged half-brother of Jong-un – who was assassinated by two female assassins allegedly at the behest of the Pyongyang regime – would be sent back to North Korea following an official request. They also said that the high-profile murder would not jeopardise diplomatic ties between the two countries. Relations between North Korea and Malaysia – wherein citizens can travel between both countries without a visa – are thought to be largely cordial.

Meanwhile, Malaysian forensic experts are still examining evidence collected from the crime scene, while labs are investigating samples following a post-mortem. Medical experts will also"conduct analysis as soon as possible" to establish the cause of death.

The outcast step-brother was poisoned by an unidentified chemical substance at the Kuala Lumpur International Airport on Monday (13 February), when he was waiting for a flight for Macau. Jong-nam died while he was being taken to hospital. Police have so far detained two female suspects for allegedly carrying out the murder. Two men, believed to be accomplices in connection with the murder, have also been arrests.

North Korea Kim Jong-nam assassination
A police officer looks at his mobile phone as he stands guard outside the morgue at Kuala Lumpur General Hospital where Kim Jong Nam's body is held for autopsy in Malaysia Athit Perawongmetha/Reuters