For almost three years they have lain in a refrigerated warehouse in New Orleans – unclaimed, unwanted and, in some cases, unidentified.

Only now, as the city prepares to mark the third anniversary of Hurricane Katrina, are the last of the victims set to be laid to rest in what is expected to be the world’s biggest jazz funeral.

After delays caused by funding problems, bureaucracy and a remarkable scientific operation to put names to the remains, the 85 dead will be fêted on their final journey by brass bands and dancers before being interred at a new $1.5 million (£750,000) Hurricane Katrina memorial.

Playing his trumpet at the head of the parade – which will take place on August 29, three years to the day since the storm devastated New Orleans and the Gulf coast – will be Frank Minyard, the coroner who led the effort to identify the bulk of Katrina’s 1,800-plus fatalities.

He has taken personal responsibility for the corpses that remain after relatives either declined to take custody themselves or could not be traced. Of the 85 bodies, as many as 50 are unidentified. “It’s sad. We don’t know their names or their stories. But these people deserve their rest,” Dr Minyard toldThe Times. “The music is to show that our dear departed friend or relative is now going on to a more great and glorious reward in Heaven.”

The funeral will represent the final chapter in an extraordinary saga that began when Hurricane Katrina pounded the Gulf coast, crumbling the levees that protected New Orleans from the Mississippi River and deluging 80 per cent of the city.

Dr Minyard, who rode out the storm outside the city, swam through chest-high water for four hours to reach his office, hoping to salvage important records and to help his staff. He was stranded for four days without food or drinking water before being rescued by helicopter. Then he moved into a caravan in the grounds of a makeshift mortuary set up outside the city to process the dead. Experts were drafted in to carry out meticulous DNA investigations.

Even when positive identifications were made, not everyone welcomed the dead home. “Some families, for various personal reasons, don’t want anything to do with their relatives,” Dr Minyard said. “You call up a family and say a relative’s been the victim of murder, for example, and they say, ‘I don’t want that no-good so-and-so’. So we take care of them.”

Joe Primo, president of the Institute on Religious Deathcare and Spiritual Healing, accused Dr Minyard of having held the 85 bodies “hostage in a warehouse”. He said: “If he wanted to give these people a proper burial he could have done it a year ago.”

Dr Minyard admitted: “The problem with it taking so long was strictly my fault, my office. We used to have thirty-five staff before the storm, now we have nine, yet the homicide rate is the same as it was before and we have more people dying without doctors in attendance, so they need to be autopsied. We have more work and less people.”

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