The Malaysian police are seeking a senior official at the North Korean embassy in Kuala Lumpur in connection with the killing of Kim Jong-nam, media reported on Wednesday.

Three North Korean suspects were being sought, in addition to the previously announced suspects, and were believed still to be in the country, media quoted Malaysian Police Chief Khalid Abu Bakar as saying.

One is the second secretary in the North Korean embassy in Kuala Lumpur, whom he named as Hyon Kwang Song.

Kim, the half-brother of North Korean leader Kim Jong-un, died last week in a possible poison attack at Kuala Lumpur airport.

North Korea has demanded that Kim's body be returned to them, and has angrily objected to Malaysia conducting an autopsy on the body, the report added.

Malaysia has cited the need to carry out an investigation as Kim died on its soil.

Both countries had enjoyed close relations, which have since become strained over the incident.