Sararat Rangsiwuthaporn, one of the country’s worst serial killers, was convicted of poisoning her friend with cyanide in the first trial.

A court in Bangkok on November 20 sentenced Sararat Rangsiwuthaporn, 36, to death for poisoning her friend Siriporn Kanwong.

The two met near Bangkok in April 2023 to release fish into the Mae Klong River. Siriporn collapsed on the riverbank and died. Her phone, money and handbag were missing. Investigators found traces of cyanide on her body.

Last year, police said they collected fingerprints and other evidence from Sararat’s Toyota Forerunner, which authorities were then able to link to unsolved cyanide poisonings dating back to 2015.

An online gambling addict, Sararat is accused of swindling thousands of dollars from his victims before killing them with chemicals.

According to police, Sararat borrowed money from her victims, then killed them and stole their jewelry and mobile phones. She committed the crime by luring 15 people to drink “herbal pills” laced with poison, only one of the victims survived by vomiting.

Police escort Sararat Rangsiwuthaporn to the criminal court in Bangkok in April 2023. Photo: Royal Thai Police

Sararat faces 13 separate trials for murder, some 80 counts.

Sararat’s ex-husband, police lieutenant colonel Vitoon Rangsiwuthaporn, was sentenced to 16 months in prison and her former lawyer was sentenced to two years in prison for complicity in Siriporn’s murder.

Sararat divorced but still lived with her ex-husband. Police said Vitoon was likely involved in the murder of Sararat’s ex-boyfriend Suthisak Poonkwan. After Sararat killed Suthisak, Vitoon picked her up in his car and helped blackmail Suthisak’s friends.