Police in Thailand have concluded their investigation into Sararat Rangsiwuthaporn, the woman accused of murdering 14 people with cyanide. The cyanide serial killer: Sararat, 36, faces about 80 criminal charges, including 14 counts of premeditated murder, for killing 14 people in eight provinces by allegedly mixing cyanide into their food between 2015 and 2023, according to Thai police. This is a historic case in Thailand.