Nearly seven decades after the battered body of a young boy was found stuffed inside a cardboard box, US police have revealed his identity.

Joseph Augustus Zarelli was the victim of one of Philadelphia’s most notorious cold cases.

The child’s naked, badly bruised body was found on 25 February 1957, in a wooded area of Philadelphia’s Fox Chase neighbourhood.

Now police have finally discovered his identity, and they hope it will bring them one step closer to finding the boy’s killer and give the victim – known to generations of Philadelphians as the “Boy in the Box” – a measure of dignity.

“When people think about the boy in the box, a profound sadness is felt, not just because a child was murdered, but because his entire identity and his rightful claim to own his existence was taken away,” Philadelphia Police Commissioner Danielle Outlaw said at a news conference.

She said the city’s oldest unsolved homicide has “haunted this community, the Philadelphia police department, our nation, and the world” for almost 66 years.

The homicide investigation remains open, and authorities said they hoped publicising Joseph’s name would spur a fresh round of leads.

Police said both of Joseph’s parents are dead, but that he has living siblings.

When the boy was discovered, he was four years old, and had been wrapped in a blanket and placed inside a large box.

Police say he was malnourished and had been beaten to death.

The boy’s photo was put on a poster which was hung all over the city as police worked to identify him and catch his killer.

The leads, the clues and the dead ends

Detectives pursued and discarded hundreds of leads – that he was a Hungarian refugee, a boy who’d been kidnapped outside a Long Island supermarket in 1955, a variety of other missing children.

They investigated a pair of travelling carnival workers and a family who operated a nearby foster home, but ruled them out as suspects.

An Ohio woman claimed her mother bought the boy from his birth parents in 1954, kept him in the basement of their suburban Philadelphia home, and killed him in a fit of rage.

Authorities found her credible but couldn’t corroborate her story – another dead end.

Generations of police took up the case.

Exhumation

They got permission to exhume his body for DNA testing in 1998 and again in 2019, and it was that latest round of testing, combined with genetic genealogy, that gave police their big break.

Dr Colleen Fitzpatrick, president of Identifinders International, a company that uses forensic genetic genealogy to help law enforcement investigate cold cases, said the victim’s DNA was so degraded that it took two-and-a-half years of work to be able to extract enough data to perform the genealogy.

The test results were uploaded to DNA databases, leading to a match on the child’s maternal side.

Authorities obtained a court order for vital records of any children born to the woman they suspected was Joseph’s mother between 1944 and 1956, and found Joseph’s birth certificate, which also listed the name of his father.

Headstone will finally have a name

Originally buried in a pauper’s grave, the boy’s remains now lie just inside the front gate at Ivy Hill Cemetery, under a weeping cherry tree, and a headstone designates him as “America’s Unknown Child”.

Services have been held there each year on the anniversary of the boy’s discovery inside the box.

People often leave flowers and, this time of year, Christmas decorations and toys.

“The boy has always been special to all of us, because we don’t know who it is,” Dave Drysdale, the cemetery’s secretary-treasurer, said.

Now they do. And now that he has a name – his real name – it will be etched on the stone.