Woman accused of poisoning 14 friends with cyanide sentenced to death in first murder trial

A woman believed to be among the worst serial killers in Thailand has been sentenced to death for poisoning a friend with cyanide.

A woman believed to be among Thailand’s worst serial killers has been convicted and sentenced to death for poisoning a friend with cyanide – in the first of her 14 murder trials.

Sararat Rangsiwuthaporn, dubbed “Am Cyanide” by media, is accused of murdering 14 friends with the chemical after swindling them out of thousands of dollars.

A court in Bangkok convicted the 36-year-old online gambling addict on Wednesday for fatally poisoning her friend Siriporn Kanwong.

According to the victim’s mother, Sararat – who pleaded not guilty to all charges – was said to be smiling as the sentence was being read aloud, the BBC reports.

Sararat Rangsiwuthaporn is accused of killing 14 friends with cyanide. Picture: Royal Thai Police/EPA/AAP

Sararat and Siriporn met up near Bangkok in April last year to release fish into the Mae Klong river as part of a Buddhist ritual.

Siriporn collapsed and died shortly after a meal with Sararat.

Investigators claimed Sararat made no effort to help her friend, and later found traces of cyanide in her body and her phone.

Police were then able to link Sararat to previously unsolved cyanide poisonings going back as far as 2015, officers said.

“The court’s decision is just,” Siriporn’s mother, Tongpin Kiatchanasiri, told reporters following the verdict.

“I want to tell my daughter that I miss her deeply, and justice has been done for her today.”

Sararat was ordered to pay Siriporn’s family $2 million baht ($A88,000) in compensation.

Police were able to link Sararat to unsolved cyanide poisonings going back as far as 2015. Picture: Thailand Police

Siriporn' Khanwong’s mother holds a picture of her daughter while talking to the media outside court. Picture: Narong Sangnak/EPA/AAP

‘Herb capsules’

Police said Sararat funded her gambling addiction by borrowing money from her victims – in one case as much as 300,000 baht (nearly $A13,000) – before killing them and stealing their jewellery and mobile phones.

She allegedly lured 15 people – one of whom survived – to take poisoned “herb capsules”, they said.

Sararat faces 13 more separate murder trials, and has been charged with around 80 offences in total.

Her ex-husband – a police lieutenant-colonel – was given 16 months in prison and her former lawyer two years for complicity in Siriporn’s killing, the lawyer for the victim’s family said.

Thailand has been the scene of several sordid and high-profile criminal cases.

Earlier this year, six foreigners were found dead in a luxury Bangkok hotel after a cyanide poisoning believed to be connected to debts worth millions of baht.

The use of cyanide is heavily regulated in the country and those found to have unauthorised access to the poison could face up to two years in jail.

The poison acts by starving the body’s cells of oxygen, which can induce heart attacks. Early symptoms include dizziness, shortness of breath, and vomiting.