Mark Riebe was convicted of killing Donna Callahan and is currently serving a life sentence in a Florida prison
Mark Riebe, 56, is serving a life term in Florida’s Blackwater River Prison for the murder of pregnant mother Donna Callahan.
Police believe Riebe is one of the most prolific serial killers despite recanting his confession that he had killed 12 women.
Riebe’s half-brother Alex Wells confessed to the police of the murder of Ms Callahan, who had vanished from a convenience store in Gulf Breeze, Florida in 1988.
He admitted to the killing and led police to where her body was buried and implicated Riebe in the murder saying he had strangled the woman in the back of the car after they had kidnapped her together.
A police tape of Alex’s confession, revealed they had taken Donna in their car and were driving along when Mark climbed over into the back seat.
He painted the picture of that evening: “I heard her saying ‘no don’t do this to me’ at first. I don’t know how to describe the sound, it was like a… sounded like to me that he had cut her throat or something.
“I don’t know, it just sounded like a real fleshy sound. And when I hear that and I turned around she had foam in her mouth. It took him a while before she quit.”
Riebe had strangled her as she begged for the life of her unborn baby before burying her in a shallow grave close by, so that he could visit it whenever he wanted.
Donna’s body was discovered 350 yards from Riebe’s childhood home where he lived with his mother and siblings in northern Florida.
Over a period of four years Riebe told detectives gruesome details of how he killed 12 other women of women aged 15-35.
He admitted to abducting and murdering mother-of-two Pamela Ray, 36, calling her father and telling him of his crime before later saying he had no recollection.
Riebe also made claims about Bonnie Gayle Ryther, 27, in 1978, and Jacqueline Brant, 18, in 1986.
However, he later recanted his confessions, claiming that he had been tricked by an agent working on his case.