The estranged half-brother of North Korea's leader Kim Jong-Un was poisoned with the lethal nerve agent VX in a brazen Cold War-style killing on February 13 at Kuala Lumpur International Airport.
Two women -- one Vietnamese and one Indonesian -- have been arrested and charged with the murder. Airport CCTV footage shows them approaching the victim and apparently smearing his face with a piece of cloth.
Investigators are also seeking seven North Korean suspects, four of whom left Malaysia on the day of the murder. The police chief has said he believes they fled to Pyongyang while the other three are hiding in North Korea's embassy in Kuala Lumpur.
"We... Are hoping to get them through Interpol."
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The red notice alerts police in Interpol member countries to share any information on the suspects with a view to potentially arresting and extraditing them to face justice. North Korea is not part of that network.
The Interpol notice posted online shows four North Korean men aged between 32 to 56 years old. They are named as Hong Song Hak, Ri Ji Hyon, O Jong Gil and Ri Jae Nam.
Seoul has blamed Pyongyang for his death, but the North has rejected those claims and has never confirmed the identity of the victim, who was carrying a passport bearing the name of Kim Chol when he was attacked.
Malaysia officially confirmed his identity on Friday, later revealing that authorities used his fingerprints and a DNA sample from one of his children to do so.
The killing has triggered a bitter row between Malaysia and North Korea, which have expelled each other's ambassadors.
Kim's wife and children, who were living in exile in the Chinese territory of Macau, went into hiding after the murder. There are fears his 21-year-old son, Kim Han-Sol, could be targeted next.