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All 15 reported victims of accused serial killer Sararat “Aem” Rangsiwuthaporn — 14 of whom died and one who survived — had been poisoned, deputy national police chief Surachate Hakparn has confirmed.
Money was the main motive for the killings, Pol Gen Surachate said.
“Aem had poisoned all 15 victims with cyanide that was placed in drinking water, food or medicines in the form of capsules. Financial problems were the motive for carrying out the cyanide murders. Aem was failing financially. She had huge debts from credit cards,” he said during a briefing on the investigation at the Royal Thai Police Sports Club on Vibhavadi Rangsit Road on Wednesday.
A sacked police officer who is the ex-husband of the suspect has confessed to two charges in connection with the case, added Pol Gen Surachate.
Pol Lt Col Withoon Rangsiwuthaporn, who was arrested this week, had given useful statements after being questioned further, the deputy chief said.
Ms Sararat, 36, dubbed “Aem Cyanide”, was arrested on April 25 at the government complex on Chaeng Watthana Road in Bangkok on a warrant issued by the Criminal Court. She is currently four months pregnant.
The arrest followed a complaint filed by the mother and elder sister of Siriporn “Koy” Khanwong, 32, of Kanchanaburi. Siriporn collapsed and died beside the Mae Klong river in Ban Pong district of Ratchaburi, where she had gone with Ms Sararat to release fish for merit-making on April 14. Cyanide was found in her body.
Investigators believe Ms Sararat mixed cyanide in Siriporn’s food, causing her death. She allegedly also stole from the victim.
National police chief Pol Gen Damrongsak Kittiprapas said there were now 15 reported cases linked to Ms Sararat — 14 of the victims had died and one survived. Of the 14 dead victims, 12 were women and two were men. Another two or three cases are being investigated, he added.
A meeting of all parties involved in the investigation had agreed to transfer all 14 cases to the Crime Suppression Division (SCD) with Pol Gen Surachate serving as the head of the investigation team, said the chief.
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Although there were no witnesses who saw Ms Sararat putting cyanide in food or drinking water for victims to consume, police investigators had sufficient circumstantial evidence, witnesses and forensic evidence to prosecute her in all cases, said Pol Gen Damrongsak.
Pol Gen Surachate went to question Ms Sararat, accompanied by her ex-husband, at the Central Women’s Correctional Institution in Bangkok, on Thursday afternoon. However, the accused declined to discuss her case.
Her ex-husband earlier in the day made a court appearance at which police opposed bail. However, the Nakhon Pathom Provincial Court approved his temporary release, saying investigators had yet to find evidence that linked him to the crimes his ex-wife is accused of.
Pol Lt Col Withoon, the deputy superintendent of the Suan Phueng station in Ratchaburi, has been fired from the force and charged with receiving stolen property, jointly forging official documents and jointly using forged official documents.
Dead ex-boyfriend
Investigators had sought an arrest warrant for the 39-year-old policeman after learning that he had picked up his former wife in Udon Thani after the death of her boyfriend, Sutthisak “Dae” Phoonkhwan.
The pair then took Sutthisak’s white Chevrolet Captiva from the northeastern province to Nakhon Pathom where they pledged it as loan collateral, said Pol Gen Surachate.
Even though the couple had divorced, they still lived together, partly because they had two children — a 13-year-old girl and a 10-year-old boy — to care for. She began a relationship with Sutthisak as she wanted his assets, said the deputy police chief.
After Sutthisak died, he said, Ms Sararat and her ex-husband went to collect debts from those who had borrowed money from her boyfriend. The family of Sutthisak, an otherwise healthy 35-year-old, believe that he too was poisoned.
Mistress questioned
Pol Lt Col Withoon has not yet admitted to having colluded with Ms Sararat in murder. But police on Wednesday questioned his mistress — identified in Thai media by her nickname “Noina” — about a possible link to one of the deaths.
Ms Sararat, her ex-husband and his mistress, who were all close, went to Hua Hin together after the murder in Ban Pong district of Ratchaburi, according to Pol Gen Surachate. They visited the resort town in an attempt to establish an alibi for Ms Sararat and show she was not near the crime scene at the time, he said.
An earlier search of a police residence in Kanchanaburi where Pol Lt Col Withoon stayed from time to time turned up some of his ex-wife’s clothes and a bottle containing a black liquid, which was found at a garbage burning site near the house.
Victims identified
According to Thai Rath, police say most of the victims were linked to the suspect over money lending, mortgaging of cars and gold. Charges against Ms Sararat are pending so far in connection with 13 premeditated murders:
- Policewoman Pol Maj Nipa “Inspector Poo” Saenchan, who died in Nakhon Pathom on April 1
- Rosjarin “Jae Noi Phak” Nilhoi, a vegetable vendor in Samut Sakhon on Aug 10, 2022
- Surat Toraphap in Kanchanaburi in 2021
- Kanika Tuaecharat in Ratchaburi in 2021
- Chantharat Wongkraisin
- Policewoman Pol Capt Kanda Torai
- Maneerat “Khu Tai” (Teacher Tai) Pojanat
- Nittaya Kaewbuppa
- Pusadee “Khru Ood” Samboonmee
- Sutthisak “Dae” Phoonkhwan
- Darinee “Fa” Thepthawee, who died in Nakhon Pathom in December 2020
- Sawittree “Nim” Budsrirak, 41, who died in 2020 in Mukdahan
- Siriporn “Koy” Khanwon (premeditated murder and theft)
As well, a charge of attempted murder is pending in connection with the poisoning of Kantima Paesa-ard in Kanchanaburi.
Seven-year-old mystery
The 15th case being investigated is that of Monthathip “Sai” Khao-in, 37, who died seven years ago in the Thong Lor area of Bangkok. Her mother Ladda, 64, of Kamphaeng Phet, met Pol Gen Surachate on Monday to discuss her suspicions that the death was linked to Ms Sararat, who was a friend of her daughter.
Pol Maj Gen Namkiat Theerarotjanaphong, a commander of the Metropolitan Police Bureau, confirmed on Thursday that the death was being investigated.
According to her mother, Monthathip and Ms Sararat often went to make merit together. Her daughter often lent money to the suspect. Monthathip had been living abroad with her husband for about three years before making a trip back to Thailand. On the day she arrived, Ms Sararat picked her up at the airport and drove her home. A few hours later she was dead.
Ms Sararat did not attended the funeral or cremation of her friend. Ms Ladda later contacted Ms Sararat to ask about her daughter’s assets. Ms Sararat reportedly spoke to her harshly and said that Monthathip’s husband had asked her to sell them.
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