A fourth suspect was arrested in connection to the North Korean leader’s half-brother, Malaysian police announced Saturday.
A man was arrested with an ID card that identified him as 46-year-old Ri Jong Chol. He was picked up Friday night.
Authorities were still trying to piece together details of the case.
Officials performed a second autopsy on Kim Jong Nam, the estranged half-brother of North Korean leader Kim Jong Un, because the first procedure was considered inconclusive, an official said on Saturday.
North Korea has vowed to reject the results of any post-mortem and demanded that Malaysia turn over the body immediately.
Pyongyang's ambassador said on Friday, while speaking to reporters that Malaysian officials may be "trying to conceal something" and "colluding with hostile forces."
Kim Jong Nam suddenly fell ill at the Kuala Lumpur airport on Monday as he waited for a flight home to Macau. He told medical workers at the airport he had been sprayed with a chemical. He died on the way to the hospital.
South Korea has accused its enemies in North Korea of dispatching a hit squad to kill Kim Jong Nam at the airport in Kuala Lumpur, saying two female assassins poisoned him and then fled in a taxi.
On Friday, Indonesia's police chief said the Indonesian woman arrested for suspected involvement in the killing was duped into thinking she was part of a comedy show prank.
The Indonesia police chief cited information received from Malaysian authorities, saying that Siti Aisyah, 25, was paid to be involved in "Just For Laughs" style pranks, a reference to a popular hidden camera show. The official said she and another woman performed stunts which involved convincing men to close their eyes and then spraying them with water.
"Such an action was done three or four times and they were given a few dollars for it, and with the last target, Kim Jong Nam, allegedly there were dangerous materials in the sprayer," the police chief said. "She was not aware that it was an assassination attempt by alleged foreign agents."
Malaysian police were questioning four suspects — Aisyah, another woman who carried a Vietnamese passport; a man they said is Aisyah's boyfriend; and the North Korean man.
North Korea broke its silence on the case Friday night. Speaking to reporters gathered outside the morgue in Kuala Lumpur on Friday, North Korean Ambassador Kang Chol said Malaysia conducted the autopsy on Kim Jong Nam "unilaterally and excluding our attendance."
Kang said the fact that Malaysia has yet to hand over the body "strongly suggests that the Malaysian side is trying to conceal something which needs more time and deceive us, and that they are colluding with the hostile forces towards us who are desperate to harm us."
Kim Jong Nam was estranged from his younger half-brother, the North Korean leader. He reportedly fell out of favor when he was caught trying to enter Japan on a false passport in 2001, saying he wanted to visit Tokyo Disneyland.
The Associated Press contributed to this report.