Kim Jong-Nam died after an unidentified liquid was sprayed in his face at Kuala Lumpur International Airport.
PIC: Members of the media are seen outside the North Korean embassy in Kuala Lumpur. (AFP)
Malaysian police investigating the assassination of Kim Jong-Un's half-brother said Sunday they were seeking four more North Korean suspects who had left the country on the day of the killing.
Kim Jong-Nam died after an unidentified liquid was sprayed in his face at Kuala Lumpur International Airport on Monday, in an attack which South Korea said was orchestrated by its northern neighbour.
The case has sparked a diplomatic row between Pyongyang and Kuala Lumpur, after Malaysia rejected demands quickly to hand the body over to the North.
Apart from the four, Deputy Inspector-General of Police Noor Rashid Ibrahim told a press conference that three further North Koreans were being sought to assist with enquiries.
Officers have already arrested one North Korean, a Malaysian man and a Vietnamese woman, as well as an Indonesian woman.
The 46-year-old North Korean named Ri Jong Chol was identified at the press conference as an IT worker living in Kuala Lumpur.
Pyongyang has demanded Jong-Nam's body be returned but Malaysia has said it must remain in the country until it is identified through a DNA sample from a family member.
"We are trying very hard to get the next of kin to come and assist us in the investigation," said Noor Rashid, but no such family member had yet come forward.
Police were still waiting for the results of an autopsy conducted on Wednesday, he said.
The deputy police chief refused to comment on any political motive for the killing, saying only that investigations were ongoing.
After Malaysia ignored demands to return the remains, Pyongyang accused Kuala Lumpur of conspiring with its enemies and said it would reject whatever findings emerged from the post-mortem.
Malaysia's health minister said he was "not bothered" by the North's complaint and added it could take around two weeks for the toxicology report to come through.
Indonesian suspect Siti Aishah, 25, worked as a masseuse at a spa, police said Sunday, while the 28-year-old Vietnamese passport-holder was employed as an "entertainment outlet employee".
Indonesian Police Chief Tito Karnavian said he had information from Malaysia that Aishah was tricked into thinking she was simply taking part in pranks for a reality TV show, but Noor Rashid would not comment on the claim.
The drama erupted on Monday as Jong-Nam prepared to board a plane to Macau, where he has been living in recent years. Malaysian police say the 45-year-old was jumped by two women who squirted liquid in his face.
Jong-Nam told staff he was suffering from a headache and was taken to the airport clinic grimacing in pain, according to Malaysian media citing CCTV footage from the airport.
He was once thought to be the natural successor to his father, the then-North Korean leader Kim Jong-Il.
But after Jong-Il's death in 2011 the succession went instead to his younger half-brother Kim Jong-Un.
Reports of purges and executions have emerged from the current regime as Jong-Un tries to strengthen his grip on power in the face of international pressure over his nuclear and missile programmes.
South Korea has cited a "standing order" from Jong-Un to kill his sibling, and a failed assassination bid in 2012 after Jong-Nam criticised the regime.