"There is strong evidence for viewing a heart attack as the cause of death", Ri asserted.
The government was implementing the change on the grounds of national security, Malaysian news agency Bernama quoted deputy prime minister Ahmad Zahid Hamidi as saying. CCTV footage from the airport terminal showed a woman approaching him from behind and wrapping a cloth around the face of a startled Kim Jong-nam.
Heung Kwang said North Koreans in their 50s and 60s knew of Jong Nam, who was once considered Jong Il's successor, adding that they were "enraged by Kim Jong Un's murder of his own brother".
He was released earlier in the morning from the Sepang police station, where he had been held, and brought to the immigration department headquarters in Putrajaya, Malaysia's administrative capital. This further fueled speculation that North Korea orchestrated the attack, and USA officials and South Korean intelligence said the plot was organized by North Korean agents.
Kim Jong Nam was waiting at the departure hall of the airport when he was assaulted by two women, a Vietnamese and an Indonesian, who wiped his face with a liquid, identified by an autopsy as VX. Being an extremely toxic organophosphate, it is classified as a weapon of mass destruction by United Nations Resolution 687.
While Malaysian authorities have never directly accused North Korea of being behind the February 13 murder, on Thursday, Kuala Lumpur proceeded to scrap visa-free entry for North Koreans, Associated Press reported.
In the report broadcast Thursday from Seoul, Thae says "North Korea is a society ruled in terror".
Only one has been apprehended, a man named Ri Jong Chol, who was released on Friday due to insufficient evidence and set to be deported after a week in custody. Section 302 revolves around murder charges while Section 34 means that a collective criminal act will be liable for an act done by him or her alone.
Ri was arrested days after Kim suffered an agonising death when he was attacked as he waited to board a flight to Macau. He reportedly fell out of favour with their father, the late Kim Jong Il, in 2001, when he was caught trying to enter Japan on a false passport to visit Tokyo Disneyland.
North Korea has a long history of ordering killings of people it views as threats to its regime. Malaysia has stepped up checks at all border crossings for North Koreans linked to the case, police have said.