Malasian police investigating the killing of the half-brother of North Korea’s leader arrested a woman yesterday.

Police in Kuala Lumpur said the woman had a Vietnamese passport.

Her arrest came around 24 hours after news broke of the death of Kim Jong Nam, the elder half-brother of North Korean leader Kim Jong Un, with reports saying female assassins had sprayed toxins in his face at Kuala Lumpur International Airport.

CCTV images, purportedly of one of the suspects, showed an Asian woman wearing a white top with the letters “LOL” emblazoned on the front.

Malaysian police chief Khalid Abu Bakar said 28-year-old Doan Thi Huong was arrested at the airport yesterday morning.

The suspect was “positively identified” from CCTV footage at the airport and was alone at the time of arrest, Khalid said.

Meanwhile, pathologists were examining the body for clues as to how he died.

South Korea’s spy chief Lee Byung Ho said the two women struck on Monday morning as Kim was preparing to board a flight to Macau where he has spent many years in exile.

Malaysian police said Kim, 45, was walking through the departure hall when he was attacked.

“He told the receptionist ... someone had grabbed his face from behind and splashed some liquid on him,” Selangor State’s criminal investigation chief Fadzil Ahmat was reported as saying by 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,” he said. “At the clinic, the victim experienced a mild seizure. He was put into an ambulance and was being taken to the Putrajaya Hospital when he was pronounced dead.”

An autopsy at Kuala Lumpur Hospital’s forensics department was completed by yesterday evening, Selangor Police Chief Abdul Samah Mat said, but no results had yet been issued.

A car bearing the North Korean flag was seen outside the department, and four officials wearing flag pins were observed in the forensics compound.

The officials left the department around 8pm without commenting to reporters.

No party had yet laid claim to the body, Abdul Samah said. “As for now the body will be kept at the Kuala Lumpur morgue.”

At a regular press conference, Chinese foreign ministry spokesman Geng Shuang said that Beijing was aware of the incident.

“According to our understanding, the incident took place in Malaysia and the Malaysian side is investigating this issue. We are following the developments,” he said.