A 28-year-old woman carrying a Vietnamese passport was arrested at a Kuala Lumpur airport yesterday, as Malaysian police continued their investigation into the death of Mr Kim Jong Nam that some say is an assassination carried out by agents of North Korea.
Mr Kim is the estranged older half-brother of North Korean leader Kim Jong Un.
The woman is believed to be one of the two women suspected of carrying out the fatal attack on Mr Kim on Monday morning as he was about to board a flight to Macau, where he lived for many years. The police are also looking for four men.
"The suspect was positively identified from the CCTV footage at the airport and was alone at the time of the arrest," police chief Khalid Abu Bakar told reporters yesterday.
An image circulating online of a woman in a white top with "LOL" on the front is believed to be that of one of the alleged killers.
A taxi driver whose vehicle the two women took after the attack is helping with police investigations.
Malaysian police believed that the woman went to the airport to take a flight back to Vietnam. Her passport identified her as Doan Thi Huong.
According to The Sun daily, she had stayed at a hotel 20 minutes away from the KL International Airport 2 (KLIA2) since Monday. It also said CCTV footage showed the other suspects, aged between 20 and 50, at the airport on Monday.
Yesterday, a post-mortem was carried out at the Kuala Lumpur Hospital to determine the cause of death. Cars belonging to the North Korean Embassy were seen at the hospital. Police would not comment when asked whether the body would be handed over to his family in Macau or to North Korea, which wants to claim it.
The passport found on Mr Kim identified him as Kim Chol, a 46-year-old from North Korea. Mr Kim, who travelled widely, was known to use fake passports.
Airport operator Malaysia Airports Holdings yesterday gave the assurance that KLIA2 is safe, calling Monday's incident an isolated one.
There have been conflicting reports about how poison - which a police officer said was "more potent than cyanide" - was administered to Mr Kim. Initial reports on Tuesday said he was killed by poisoned needles, but Mr Kim apparently told airport staff that some liquid was splashed on him.
"He told the receptionist (at the counter of KLIA2)... someone had grabbed his face from behind and splashed some liquid on him," Selangor state's criminal investigation chief Fadzil Ahmat told The Star newspaper.
"He asked for help and was immediately sent to the airport's clinic. At this point, he was experiencing headache and was on the verge of passing out," said Mr Fadzil. "At the clinic, the victim experienced a mild seizure." He died while being taken to Putrajaya Hospital.
A South Korean lawmaker said yesterday that Mr Kim's family - his former and current wives and three children - are living in Beijing and Macau, and are under the protection of the Chinese authorities.
China is North Korea's main ally. Asked about the case, a Foreign Ministry spokesman yesterday would only say that Beijing was monitoring developments closely.
South Korea's spy agency, meanwhile, confirmed yesterday that Mr Kim was killed with poison, and that Pyongyang agents had a "standing order" to assassinate him in the past five years. Mr Kim, who lived outside North Korea for over a decade, was a critic of the Kim Jong Un regime and had openly criticised the political system.
South Korea's acting President Hwang Kyo Ahn said Mr Kim's murder, if confirmed to be carried out by Pyongyang, is a "telling sign of the North Korean regime's brutal and inhumane nature".
• Additional reporting by Chang May Choon in Seoul