Pair Admit Manslaughter After Poisoning Men in Gloucestershire and Oxfordshire
Adina Mihai, 31, and Madalin Dumitru, 30, have admitted the manslaughter of an 80-year-old man from Gloucestershire and a 37-year-old man from Oxfordshire. The pair targeted men seeking sexual services between August 2024 and July 2025, with Mihai posing as a sex worker and administering a deadly amount of the sedative GBL to the victims.
Mihai and Dumitru, formerly from Ilford in Essex, took financial deposits from their victims before Mihai met them at their homes. She secretly gave them GBL (gamma-butyrolactone), which converts into GHB (gamma-hydroxybutyrate) in the body, a powerful sedative and sleep-inducing agent.
Victims Identified
Malcolm King, 80, from a village near Cirencester in Gloucestershire, was found dead at his home on 21 August 2024. Gary Mouat, 37, was found dead at his property in Banbury on 13 July 2025. Initially, King's death was deemed non-suspicious due to a pre-existing health condition, but further toxicology tests revealed Mihai had poisoned him with GBL.
Detectives from Thames Valley Police's major crime unit ascertained that Mihai poisoned Mouat by adding GBL to an alcoholic drink. A bulletin was issued to all UK police forces to check for any other unexplained deaths linked to the pair.
Other Victims and Guilty Pleas
Thames Valley Police also discovered two surviving victims from the south of England whom Mihai and Dumitru had drugged and stolen from. They cannot be named for legal reasons. No other deaths, poisonings, or thefts have been linked to the pair, but police are keeping an open mind about other possible victims.
At Oxford Crown Court on Wednesday, the pair appeared via video link and pleaded guilty to the manslaughter of both men and to two further counts each of administering poison.
Police Statements
Det Insp Adam Stacey, the senior investigating officer for Gloucestershire, said: “Adina Mihai and Madalin Dumitru targeted men who were seeking sexual services and covertly drugged to render them unconscious before stealing from them. Tragically for Mr King, their callous and calculated actions had fatal consequences.”
Det Insp Michael Roddy, of Thames Valley Police, said: “For Gary Mouat, these actions had fatal consequences so I am pleased to have got answers for his family and would like to thank them for their support throughout our investigation.”
Mihai and Dumitru have been remanded in custody and are due to be sentenced at Oxford Crown Court at a later date. They were told by Mrs Justice Brunner they will receive long jail terms.
