Kim Jong-nam killing: Senior N Korea diplomat named as suspect
Hyon Kwang Song is one of three more North Koreans being sought. One of the others is a state airline employee.
Police also confirmed Mr Kim, half-brother of North Korean leader Kim Jong-un, died after two women wiped a toxin on him at Kuala Lumpur airport.
North Korea's embassy in Malaysia angrily denied the claims.
In a statement, it said the fact that the substance was on the hands of the women proved it could not have been a poison and called for the immediate release of the "innocent females" and a North Korean man.
Speaking at a press conference in Kuala Lumpur earlier on Wednesday, Malaysian Police Chief Khalid Abu Bakar said they were looking for three North Koreans in addition to the previously announced suspects.
One of them is Hyon Kwang Song, 44, the second secretary of the North Korean embassy in Kuala Lumpur.
The others are Kim Uk II, 37, who works for Air Koryo, and another North Korean Ri Ju U.
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