Malaysian police are seeking a senior official at the North Korean embassy in Kuala Lumpur in connection with the killing of Kim Jong-nam.
Kim, the half-brother of North Korean leader Kim Jong-un, died last week at Kuala Lumpur airport.
Police also confirmed details of the killing, saying two women approached Mr Kim and wiped a toxin on his face.
There is widespread suspicion that North Korea was behind the attack, which its Malaysian envoy has denied.
Speaking at a press conference in Kuala Lumpur, Malaysian Police Chief Khalid Abu Bakar said two North Korean suspects were being sought, in addition to the previously announced suspects, and were believed to still be in the country.
One is the second secretary of the North Korean embassy in Kuala Lumpur, while the other is linked to North Korea’s state airline.
He added that the other four North Korean suspects are believed to have fled Malaysia and are in Pyongyang now, while one North Korean man remains in Malaysian police custody.
Authorities are still waiting for the results of the autopsy on Kim’s body, and are seeking Kim’s family members to provide a DNA sample.