What happened
Sararat Rangsiwuthaporn, widely called “Am Cyanide” by Thai media, was accused of using cyanide in a series of deaths involving people in her social and financial circles.
The investigation
The investigation expanded after the April 2023 death of Siriporn Khanwong. Toxicology findings, financial records, cyanide purchases and evidence recovered from vehicles and belongings became central to multiple prosecutions.
What the courts or investigators concluded
By 2026, Sararat had been convicted in more than one murder trial while other cases in the wider series were still moving through the courts; she was also acquitted in at least one separate charge.
Why the case remains significant
Because the proceedings are case-by-case, the responsible way to describe the story is to distinguish murders proved in court from additional deaths alleged by police rather than treating the entire suspected total as already adjudicated.
Case context
Crime by Region organizes cases geographically so readers can move from one file to other investigations from the same country. For unresolved or contested cases, the wording above reflects the distinction between confirmed events, investigative theories and findings actually established in court.