A North Korean national has been arrested over the killing of North Korean leader Kim Jong-un’s half-brother, Malaysian police say.
The first North Korean to be arrested over Kim Jong-nam’s death was named as Ri Jong Chol, 46.
An Indonesian woman, a Malaysian man and a woman with a Vietnamese passport were detained earlier.
Police believe poison was sprayed into Mr Kim’s face as he waited to board a flight from Kuala Lumpur to Macau.
They say the latest suspect was detained on Friday evening in Selangor, near the Malaysian capital. No further details were given.
Police have finished Kim Jong-nam’s post-mortem examination, though the results have not yet been made public.
North Korea has meanwhile demanded that Malaysia immediately release the body.