Christopher Alder, 37, died in police custody in 1998 and hundreds of mourners attended what they thought was his funeral two years later.
But in an horrific blunder, which is now the subject of a criminal investigation, Mr Alder’s body was discovered in the mortuary at Hull Royal Infirmary when the family of a Nigerian woman, 77-year-old Grace Kamara, arrived to view her body before her funeral, which was due to take place last Friday.
It appears she may have been buried in Mr Alder’s place.
The Alder family’s anguish was compounded by the fact that the ashes of his 25-year-old niece, Laura, were scattered over the grave, which may now have to be dug up.
Mr Alder’s sister Janet said she was outraged that the family had still not been able to see the body in the morgue to independently verify its identity a week after the error was discovered.
She has been told the body was subsequently identified by a deputy coroner, but that the identification tags have since been removed, which was possibly done as part of the police investigation.
She said: “Because they have got the wrong body before I don’t feel very confident that unless there is independent identification by us as a family that they are not going to repeat the mistake.
“Somebody needs to physically see Christopher, and maybe there should be DNA tests, because I just can’t accept what they are saying.
“Yesterday, I was told they had taken the tags off the body and that made me so, so angry because there’s been no formal identification on behalf of the family.
“They say they are 100 per cent sure it’s Christopher but why should we believe them? I don’t particularly want to do it but it needs doing once and for all to make sure it’s the right body.”
An investigation by the Yorkshire Post two years ago revealed that a body had lain in Hull Council’s mortuary for 10 years and that the deceased’s next of kin were in Nigeria.
At the time, the city council declined to reveal the identity of the corpse, but said it was taking steps to resolve the “unusual situation”.
Mrs Kamara died of natural causes at her home in Hull in 1999. Her relatives had travelled from Africa to finally attend her funeral last week and had even gathered at the city’s Eastern Cemetery before the burial had to be cancelled.
It appears the blunder may only have been discovered because of the Benin culture into which Mrs Kamara was born, which requires relatives to see a body before it is buried.
Mr Alder was taken to hospital after being concussed in a scuffle outside a nightclub but police were called when he became aggressive.
The former paratrooper choked to death on blood and vomit with his arms handcuffed behind his back and his trousers around his ankles as he lay on the floor of the police station.
A report by the Independent Police Complaints Commission found the conduct of four officers who were present at the time amounted to “unwitting racism” and the “most serious neglect of duty”.
The investigation into the body mix-up is being carried out by South Yorkshire Police on behalf of Humberside Police. Both forces declined to comment.
A spokesman for Hull and East Yorkshire Hospitals NHS Trust, which runs the morgue, said: “The investigation is now being handled by South Yorkshire Police and the trust has not been approached directly to arrange a viewing of the body.”