The Malaysian police on Wednesday identified two more suspects in the murder of Kim Jong-nam, the estranged half-brother of North Korean leader Kim Jong-un, reported Reuters. Police Chief Khalid Abu Bakar (pictured above) said one is a senior official in the North Korean embassy while the other is related to the North Korean airline.

Both the suspects been called for questioning. “We have written to the ambassador to allow us to interview both of them. We hope that the [North] Korean embassy will cooperate with us and allow us to interview them quickly. If not we will compel them to come to us,” said Bakar, according to AFP.

Bakar added they were on lookout for four accused who had fled the country after the assassination on February 13, after having arrested one North Korean man, a Vietnamese woman, an Indonesian woman, and a Malaysian man.

Bakar also said that the two women who were arrested in connection with the case were aware that it was a poison attack. “Yes, of course they knew... The lady was moving away with her hands towards the bathroom. She was very aware that it was toxic and that she needed to wash her hands,” said Bakar. His statement’s come after the Indonesian police had claimed that one of the suspects was told that she was taking part in a TV prank show, according to AFP.

The assassination has strained bilateral relations and triggered diplomatic tension. On February 19, Malaysia had recalled its envoy to Pyongyang and summoned North Korea’s envoy, Kang Chol, for saying Kuala Lumpur authorities were colluding with “external forces” in the handling of the investigation.

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. He 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.