Police chief Khalid Abu Bakar said on Wednesday that investigators sought to question the second secretary of the embassy, as well as an employee of the North’s state airline Air Koryo.
"We have written to the [North Korean] ambassador to allow us to interview both of them. We hope that the Korean Embassy will cooperate with us and allow us to interview them quickly. If not, we will compel them to come to us,” Khalid said.
According to him, police "strongly believed” that four other suspects, who fled Malaysia on February 13 — the day of Kim Jon-nam’s murder — had arrived in the North Korean capital of Pyongyang. Three suspects were also believed to still be in Malaysia.
Kim was attacked by two female assailants as he was walking through the departure hall at the Kuala Lumpur International Airport last Monday. He died en route to the hospital.
Khalid said five North Korean suspects, who were "heavily involved” in the murder, provided the two female assassins with a toxic substance. The women, who have been arrested, were trained how to wipe the poison on Kim’s face, according to the Malaysian police chief.
The presumed assassination was captured by CCTV cameras at the airport. The footage, recently released by a Japanese broadcaster, shows one woman holding the victim from behind and the other wiping the poison on his face.
Meanwhile, the killing of Kim has sparked a diplomatic row between Kuala Lumpur and Pyongyang. The Malaysian government summoned the North’s ambassador, Kang Chol, after he accused officials in Kuala Lumpur of conspiring with "hostile forces” during the investigation.
He said the investigation was being "politicized by Malaysia in collusion with South Korea.” Malaysia has also recalled its ambassador from Pyongyang.
North Korea has demanded that Kim’s body be handed over. Malaysia has refused, demanding DNA samples from a next of kin.
Jong-nam, the half-brother of North Korean leader Kim Jong-un, had been living in exile in the Chinese city of Macau. It was not clear why he was in Malaysia. He was traveling under an alias.