Malaysian authorities on Saturday expelled North Korea’s ambassador after he refused to apologise for his allegations against the nation in Kim Jong-nam’s assassination case. Foreign Minister Anifah Aman said the Kang Chol was declared persona non grata and given 48 hours to leave the country.

The envoy had accused Kuala Lumpur of colluding with “outside powers to defame North Korea” with its handling of the murder of North Korean leader Kim Jong-un’s estranged half-brother. Malaysian authorities had demanded a formal apology for his remarks earlier in the week.

“Malaysia will react strongly against any insults made against it or any attempt to tarnish its reputation,” the foreign minister said, adding that the decision was a response to the North Korean Embassy’s failure to submit an apology or attend a bilateral meeting scheduled to discuss the case.

Meanwhile, Malaysian Police Chief Khalid Abu Bakar has said he will respond to claims made by a deported North Korean chemist against the force. The chemist, Ri Jong Chol, had alleged that Malaysian Police had threatened him to confess to killing Kim Jong-nam, AP reported. He had accused the force of threatening to kill his family unless he complied with their demands.

The development follows Malaysia’s suspension of visa-free entry for North Koreans following the February 13 murder at the Kuala Lumpur International Airport. CCTV footage showed two women attacking Kim with “poisoned needles” before fleeing the scene. The police chief said that although both the women had washed their hands before they fled the airport, one of them was suffering from its side effects. The toxin was identified as VX, a deadly chemical weapon that was used as a nerve agent.

The assassination has already strained bilateral relations between the countries and triggered diplomatic tension. On February 19, Malaysia had recalled its envoy to Pyongyang and summoned North Korea’s Kang Chol. So far, the Malaysian Police have arrested one North Korean man, a Vietnamese woman, an Indonesian woman and a Malaysian man in the case. They have also identified two other suspects – one a senior official in the North Korean Embassy and the other related to the North Korean airline.

Kim Jong-nam, the eldest son of late dictator Kim Jong-il, had challenged his half brother’s succession to the top post. Officials said he had been trying to take over the administration, but had been living in Macau under Chinese protection after a reported dispute with his father over his attempt to enter Japan with a fake passport, South Korea’s intelligence agency told its parliament.