The former wife of a senior police officer in Ratchaburi province is currently four months pregnant with the baby of her latest husband who is also believed to have died at her hands on March 12th last when the couple travelled to Udon Thani province on business. His family were later shocked by the green pallor of the man’s body with blood running from his nose while suspicions arose when it was found she had told authorities in Udon Thani that he suffered from a congenital heart defect.

A special task force headed up by Deputy National Police Chief General Surachate Hakparn has taken over the investigation into what looks increasingly like one of Thailand’s biggest serial killer cases ever. Police have unearthed so far a dozen suspicious cases involving deaths linked to 34-year-old Ms Sararat Rangsiwutthaporn or ‘Am’  which may be attributed to cyanide poisoning. Nearly all of the deceased had a financial relationship with the accused who Thai media have in recent days dubbed ‘Am Cyanide’ as the weight of circumstantial evidence grows damning against the accused. It includes missing valuables linked with all the deaths who were at close quarters with the suspect before their untimely demise. Ms Sararat was escorted to a Thai prison on Wednesday night, under heavy guard, for the first time after the Criminal Court denied the suspect, the ex-wife of a deputy superintendent of police in Ratchaburi, bail and remanded her in custody until May 7th. 

prolific-cyanide-serial-killer-held-in-jail-am-sararat-rangsiwutthaporn
On Tuesday, the National Police Commissioner General Damrongsak Kittiprapas appointed Big Joke or General Surachate Hakparn (centre) to take over a task force investigating cases linked to what police believe to be a prolific serial killer who used cyanide to murder her victims. Ms Am or Ms Sararat Rangsiwutthaporn (inset left and right) was arrested by police in Bangkok on Tuesday afternoon working with the Crime Suppression Division (CSD) and was found to be in possession of cyanide. She was arrested on foot of a Criminal Court warrant which charged her with intentional or premeditated murder. On Wednesday, the court denied her bail and remanded her in custody until May 7th next.

The number of suspect incidents associated with an investigation just launched this week into a possible serial killer, the former wife of a deputy superintendent of police in Ratchaburi province, has now been extended to include twelve deaths and may even go higher as police scour incident case histories and speak to a growing list of witnesses.

On Wednesday, the Criminal Court extended the period of detention of the suspect Ms Sararat Rangsiwutthaporn by a further 12 days from April 26th to May 7th next and denied a defence request for bail.

Taken to prison on Wednesday under heavy guard after the Criminal Court rejected bail and extended her detention period for 12 days until May 7th next

Ms Sararat was then taken to prison under heavy guard following her arrest on Tuesday afternoon and several health scares while initially under interrogation by the Crime Suppression Division (CSD) as the criminal investigation was upgraded through the intervention of National Police Commissioner General Damrongsak Kittiprapas.

Top brass at the Royal Thai Police first revealed that they may be dealing with a serial murder investigation after the arrest of 34-year-old Ms Sararat Rangsiwutthaporn or ‘Am’ by Crime Suppression Division (CSD) police at government offices on the Chaeng Watthana Road in Bangkok.

The initial case against Ms Sararat who Thai media have already dubbed ‘Am Cyanide’ stemmed from the death of a 32-year-old woman, Ms Siriporn Khanwong or ‘Nong Koi’ on April 14th last in Ratchaburi after the woman, a mortgage adviser, fainted and died from an apparent heart attack while releasing fish to make merit during the Songkran holidays.

The incident took place near the Mae Klong River in Ban Pong Municipality where both lived.

Death on April 14th was initially thought to have been a heart attack but then suspicions grew quickly about the involvement of Ms Am with the deceased

The death was initially attributed to a sudden heart attack by the family of the deceased woman but soon they came to suspect she was the victim of cyanide poisoning at the hands of Ms Am or Sararat whose latest husband had also died suddenly just over a month earlier,

Ms Am was the last person seen with the woman before her demise as was the case with her husband Mr Suthisak Poonkhwan who also passed away on March 12th.

On Tuesday, National Police Commissioner General Damrongsak Kittiprapas appointed Deputy National Police Chief Surachate Hakparn or ‘Big Joke’ to lead the widening investigation after the case had been handled up to that point by General Jiraphat Phuridet of the Central Investigation Bureau (CIB) up to Ms Sararat’s arrest on Tuesday.

Since then, it has been revealed that the extent of the inquiry has widened with twelve fatalities across at least six provinces being investigated by a police task force led by General Surachate.

Big Joke or General Surachate Hakparn took over the case on Tuesday by order of the police commissioner and is now coordinating a large police task force

Details about the cases being probed are still being reported.

General Surachate warned on Tuesday that many of these deaths were not originally analysed by police so the evidence will be hard to pull together.

The cases being probed go back to a death on December 13th 2020 of a woman identified as Fah in Nakhon Pathom province followed by a second death on January 16th 2021 when a deceased woman identified as Ms Surat died in the Tha Maka district of Kanchanaburi province.

The third case goes back to August 10th 2022 when a female police captain identified as Ms Kanda was also reported dead on the Petchkasem Road of Nakhon Pathom province while, just five days later, a fourth case occurred in Chaam in Phetchaburi province when a 65-year-old woman identified as Ms Chanrat died in an incident reported at her home.

The woman had handed over ฿100,000 to Ms Am before her death.

The fifth case occurred in Ratchaburi province at a PTT service station at Photharam Circle when a 44-year-old woman named Ms Kanika Tuladecharak passed away in September 2022. 

Case of Bangkok woman who died at a PTT service station while driving with Ms Am brought personally to General Surachate by her father and daughter

That case, it is understood, was the subject of a complaint filed with Deputy Chief General Surachate himself in recent days by the daughter and father of the victim who was travelling with the accused Ms Am or Ms Sararat, at the time.

The two complainants contended that Ms Am or Ms Sararat was responsible for the death of the woman.

They told the top cop that on September 11th that Ms Kanika drove from her home in Bangkok to meet Ms Sararat in Ratchaburi and that she picked up the suspected serial killer.

She then drove on with Ms Sararat in her car before expiring shortly afterwards at the PTT petrol station in the Potharam district of the province. 

Subsequently, all her personal belongings including her smartphone and gold bracelet were found to have gone missing.

Death of the suspect’s latest husband, a loan business operator, aroused suspicions in her home province of Ratchaburi after he died in Udon Thani

The sixth case and one where friends of the deceased became suspicious of the death involved 36-year-old Mr Suthisak, the operator of a loan business and reportedly the latest husband of Ms Am or Sararat who previously was divorced from a deputy superintendent at Bang Pong Police Station in Ratchaburi who since April 21st has been transferred to another police station in the province by order number 250/2566, signed by the Provincial Police Chief, Police Major General Wachiraphong Amaraphithak.

The order moved the officer from Bang Pong to Suan Phueng Police Station, also in the province, due to his wife’s growing notoriety.

Mr Suthisak died in Udon Thani while travelling with Ms Sararat at a rented dormitory unit there, on March 12th this year, just a month before 32-year-old Ms Siriporn Khanwong or Koi’s untimely demise, now believed to have been caused by cyanide being mixed in to her food by Ms Am who was living with her.

Victim’s belongings disappeared after their deaths

Police on Tuesday also pointed to multiple reports of belongings of the victims, in the complex web of cases before them, all going missing at the time of the deaths.

Further details are still coming in on additional cases including one related to a vegetable seller in Samut Sakhon in August 2022 and a teacher in Nakhon Pathom in November 2022 who was initially thought to have died of Leukaemia.

All had extended loans or handed substantial amounts of money to the suspected serial killer.

In one of his first acts after commencing the serial killer probe, General Surachate met the relatives of five of the victims who had not filed a complaint with police and had no idea that their loved ones may have been poisoned with cyanide.

Cyanide or UN 1680 is readily available in Thailand. It is reported that Ms Am was carrying a jar of the poison when arrested last Tuesday in Bangkok

Cyanide or UN 1680 is readily available in Thailand through drug firms and can be purchased online.

It is understood that Ms Sararat was carrying a quantity on Tuesday when detained by police on an arrest warrant just issued by the courts for intentional murder.

Lethal doses of the poison can induce dizziness, vomiting, headache, fast heart rate followed by a slow heart rate, reduced blood pressure and ultimately heart seizure with a particularly quick-acting effect depending on the dose with lethal doses of cyanide becoming effective within a few minutes.

On Tuesday, speaking with reporters, General Surachate said, from enquiries, it is thought the administration of cyanide in these cases may have been achieved without ingenuity by mixing the substance with food with Ms Am or ‘Am Cyanide’ being known to be a very agreeable person and extremely helpful although in recent days her more disillusioned friends have also recalled that she always tended to end conversations with a polite reminder about financial matters or pending transfers to her bank account.

Two victims of the suspected killing spree by the woman appeared to have been policewomen, something pointed out by General Surachate

General Surachate drew attention on Tuesday to the fact that two of the victims so far were policewomen and that police were disturbed by the linkages in all cases to the suspect who lived in a police residence.

He said his task force was asking police throughout the country to scan their files and forward any suspicious cases to him which may have involved Ms Sararat.

Before this, the Police Commissioner, General Damrongsak Kittiprapas indicated that the work of the Institute of Forensic Medicine will be extremely important in the case to coordinate the examination of key evidence from all cases.

He also told reporters that all the incidents seemed to have been linked to financial transactions or debt.

He said that police were also looking at whether the main suspect may have been aided in what appears to be an elaborate trail of criminal exploits.

Motive appears to be financial greed but police are also looking at the mentality of the suspect although Big Joke warned of no basis to escape justice

Speaking to the same point, General Suarchate said that police were looking at a motive of financial greed but were also examining the mental condition of the accused woman while quickly underlining his belief that this defendant was not mentally disturbed to such an extent that she may be able to claim diminished responsibility before the law.

At the same time, on Tuesday night, the main lawyer representing Ms Am, Ms Thannicha Ek Suwanwa told reporters outside Crime Suppression Division (CSD) headquarters that they foresaw no problem in defending the 34-year-old and expressed concern for her health while revealing that she had suffered high blood pressure during her period of detention at the police division headquarters.

Accused’s lawyer expressed confidence her client would be able to defend the case against her in court but worried about her health and media coverage

The lawyer expressed concern at media coverage of the case and disclosed that Ms Sararat’s blood pressure was 170/220 while also confirming that they would seek bail in court as it appeared the police intended to pursue legal proceedings against the accused in the case for intentional or premeditated murder.

Ms Thannicha also expressed concern at the drawn-out nature of proceedings saying that since her client’s arrest at 3 pm on Tuesday until 9 pm she had not yet been interrogated by officers.

Police later reported that the suspect was unresponsive to questions and uncooperative.

Concerning the case which has activated the police interest and pursuit of her client, the death of Ms Siriporn Khanwong or Nong Koi on April 14th last near a river in Ratchaburi province, Ms Thannicha stressed that her client had no disagreement or falling out with the deceased woman at all.

Mother of the woman’s latest husband met with police in Udon Thani on Tuesday linked with her son’s death and later visited the room where he died 

The key case that aroused suspicions against Ms Sararat was the death of her recent husband by whom she is now four months pregnant, 36-year-old Mr Suthisak Poonkhwan who expired on March 12th at a dormitory in Udon Thani province despite living with Ms Sararat in the Ban Pong District of Ratchaburi.

On Tuesday morning, 55-year-old Ms Wassana Tanayapan the mother of the deceased man met Police Lieutenant Colonel Thanawat Thongwilai of Udon Thani Police Station to give further testimony concerning her son’s death given the altered circumstances of the national police probe.

She said she was aware he was in a relationship with Ms Am or Sararat who was pregnant with her son’s child.

Family gave gold and cash to the pregnant widow

She revealed that the family of the deceased had given over 8 baht of gold jewellery to the woman at the funeral rites for her son after his death in March together with cash donations to care for the child.

She said there was some anxiety at the state of her son’s body which appeared to have a greenish pallor with bleeding seen from his nose.

She told reporters that she was due to visit the dormitory where he died after her meeting with the police to assist the spirit of her son to return home.

‘After that, I will go to the dormitory where my son died. Because a fortune teller came and said that the dead son wanted to go home. Can’t find the way back home. Therefore came to perform the ceremony to invite the soul of the son to return home,’ she explained.

Travelled to Udon Thani with her husband in March as he promoted his loan business. The couple stayed at a local dormitory in the northeastern town

The couple reportedly had lived together in Ratchaburi but rented the dormitory unit, number 12 Ban Nong Na Lam in the Sam Phrao Sub District of Udon Thai for one month in March as part of an effort to promote Mr Suthisak’s loan business.

This was confirmed by 35-year-old Mr Niwat Kotsanlee, the caretaker at the 2-storey building who said he was informed that the man’s wife, Ms Am, would be travelling back and forth.

The day before his death, the deceased man and his wife, March 11th last, had visited a temple in the Nong Han District by car.

During the excursion, the pair stopped at a roadside restaurant where Mr Suthisak became faint or weak after visiting the lavatory and was taken by his wife to the local Nong Han Hospital where doctors examined him before handing out a prescription for vomiting.

Manager informed that Mr Suthisak had died by Ms Sararat but was not surprised, he was made aware that the man had a bad heart condition beforehand

They asked him to take time to relax at his dormitory unit.

At the dormitory on March 12th, Ms Sararat informed Mr Niwat that her husband had died suddenly.

He said he was not surprised by this as his wife had earlier indicated that he had a heart condition.

The building supervisor found the body lying on the room’s bed with his eyes open and summoned Udon Thani police.

The main suspect, Ms Sararat told him she had just gone out to do the laundry when she returned to find her husband was dead.

Friends of new husband made a shocking discovery

Subsequently, it is reported by friends of Mr Suthisak that Ms Sararat delayed returning to Ratchaburi with her husband’s body and is reported to have celebrated her birthday alone in Udon Thani although Mr Suthisak’s mother confirmed her son’s pregnant wife had attended the religious rites for him and behaved appropriately including buying food and drinks for the monks.

After this, there emerged reports of information, found in the rented room by friends.

This was an official report into the man’s death which was withheld from the family.

It appears that Ms Sararat had told police and hospital officials that her husband suffered from an acute congenital heart condition.

There are also reports that such inquiries also led to the discovery of Ms Sararat’s links to cyanide or UN 1680 which is now at the centre of a case which could make the woman one of Thailand’s biggest serial killers.

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