Si Quey, who was convicted of killing seven children and accused of eating them, will finally be cremated, more than six decades after he died from the bullets of a firing squad.
The Corrections Department on Monday announced the cremation ceremony for Si Quey will be at Wat Bang Praek Tai in Muang district of Nonthaburi at 10am on Thursday.
Department director-general Naras Savestanan said Bang Kwang Prison will sponsor the rite. No-one had ever contacted the department with proof of a relationship with the killer. He was eventually declared a stateless person.
Si Quey was Thailand's most notorious serial killer.
He was convicted of murdering seven children and also accused of removing their internal organs and boiling and eating them. He was arrested in Rayong in 1958 and confessed to the murders, but denied the cannibalism charges.
Si Quey was executed by firing squad at Bang Kwang on Sept 16, 1959. He was just 32 years old. Siriraj Hospital took the body for medical study the same month.
His preserved cadaver was on display at the hospital's Medical Museum for medical students and the public to view. It was removed from the museum last year after a complaint by residents of Thap Sakae district of Prachuap Khiri Khan to the National Human Rights Commission that his dignity had not been protected as the exhibit branded him a cannibal.
The bodies of at least four of the children murdered and allegedly cooked and eaten by him were found in Thap Sakae district. The other murders were committed in Bangkok, Nakhon Pathom and Rayong, where he was arrested.
Siriraj Hospital replaced the label "Si Quey, Cannibal", with "Death Row Prisoner" in June last year. The exhibit was removed from public display in August.
Si Quey's name was often used by parents in the old days as a warning for children to behave: "If you misbehave, Si Quey will come and catch you."
Wat Bang Praek Tai, where he will be cremated, is one of two temples where religious ceremonies were held for inmates executed by firing squad at the prison. It is adjacent to Zone 11 of Bang Kwang Prison.
The bodies were taken out through a back door of the prison for cremation.
Si Quey was incarcerated and executed at Bang Kwang Prison.