Prison chiefs wrongly told a woman her jailed husband was dead after mistaking him for another inmate with the same surname.
Police were sent to the woman's home as staff at Frankland Prison, in Co Durham, could not reach his family by phone.
However, the heartbroken spouse was so distraught at the news officers decided to double check his identity with the jail.
It was only then that they discovered the blunder.
The "Camden Ripper" Anthony Hardy, 69, died of Covid in 2020 while serving a whole life sentencing for killing at least three people.
His sons discovered their dad was dead two days later after reading it in the news.
The Prisons and Probation Ombudsman ruled the mistake was the result of "human error" as records were updated incorrectly.
The ombudsman said the error was "unacceptable".
A Prison Service spokesman said: “We are sorry for this error.
"HMP Frankland has implemented all of the ombudsman’s recommendations to help ensure this never happens again.”
It comes two years after bungling police officers told a mum her son was dead, only for her to discover he was still alive when she phoned his number.
Wes McDonnell, from Northampton, has slammed Merseyside Police for wrongly identifying him as the man who died in a children's park in St Helens.
The dad-of-three said police 'put two and two together and got five' after finding his Facebook account and seeing he had the same name as the man found in St Helens.
Merseyside Police has apologised for any distress caused to the family, which suffered another tragedy 16 years ago, when Mr McDonnell's sister killed herself.
Mr McDonnell, 39, told Mirror Online: "Police turned up at my mum's house, sat her down and told her I was dead.
"She rang me up thinking I wasn't going to answer the phone and when I answered she was hysterical. When I picked the phone up she was crying.
"My sister committed suicide 16 years ago so you can imagine her state."
The contract manager had not replied to a message his mum sent him that morning, convincing her that he had died.
