The "sloppy mistakes" of a pathologist left a prisoner's family wrongly believing he had killed himself or been murdered just weeks before his release.

Adam Turner, 37, was told by the coroner on January 6 this year that his 58-year-old dad James, from Ipswich, had hanged himself four months earlier in Wayland Prison near Watton.

This came as a shock to the family, who were so unconvinced by the findings they strongly suspected the late Mr Turner had been murdered by another inmate.

"It was horrible. Me and my brothers were so confused," his son Adam said.

"I'd spoken to my dad three days earlier and he was in great spirits, ready for his release in two weeks time and desperate to see his new grandkids.

"I immediately thought he'd been murdered because there's no way on earth he would have killed himself right before he was due to get out of there.

"He wouldn't have done that to us."

Initially, following a police investigation, the family were assured the death was "natural", but were told there'd be a delay in finding out for certain because of a shortage of pathologists.

However when the pathologist submitted his report to the coroner on January 5, his conclusion completely contradicted what the police had found.

He attributed cause of death to hanging after apparently finding a crease on James' neck from a ligature. The family were told the devastating news over the phone.

At this point, the police were asked to review their investigation, but could find no evidence Mr Turner had taken his own life.

Upon questioning the pathologist's findings, it then became clear he had in fact mixed up the post-mortem results.

According to the coroner's office, the pathologist had been dealing with two people with near-identical names, and "regrettably" ascribed death by hanging to the wrong Mr Turner.

"The actual cause of my dad's death was heart failure," Adam explained. "But we had to go four days thinking the worst.

"I don't know how such sloppy mistakes can happen at that level."

The senior coroner's office for Norfolk said this had never happened before, and that they were working with the pathology service to prevent it happening again.

"We apologise for the distress this error has caused," their spokesman added.