Philadelphia(CNN) The "Boy in the Box" finally has a name.
Police on Thursday publicly identified a boy found dead in a box in Philadelphia 65 years ago as four-year-old Joseph Augustus Zarelli, the victim of what police say is one of the city's oldest unsolved homicides.
The identification, made through DNA analysis, represents investigators' biggest break in the decades-old cold case, which dates back to late February 1957, when the child was discovered wrapped in a blanket inside a cardboard box, exhibiting evidence "of recent and past trauma," Philadelphia Police Commissioner Danielle Outlaw said.
The case attracted "immense" public interest, Outlaw told reporters Thursday. But no one ever came forward to claim Joseph as their child, and his identity remained a mystery despite numerous attempts to identify him over the years.
That changed this week when police announced they had successfully identified the child through detective work and with the help of genetic genealogists -- a field that in recent years has led to numerous breakthroughs in cold cases, including in that of the notorious Golden State Killer, and reunited families with missing loved ones.
"For sixty-five years, the story of America's Unknown Child has haunted this community, the Philadelphia Police Department, our nation, and the world," Outlaw said, who opened Thursday's news conference by praising generations of police officers who worked the case, some of whom are no longer alive. "Despite the fact that Joseph Augustus Zarelli's entire identity and rightful claim to his own existence was taken away, he has never been forgotten."
Officials are hopeful the techniques used to identify Joseph after so many years will assist them in other cold cases and those in the future; the breakthrough "brings hope that there will never again be an unidentified victim of homicide in the City of Philadelphia," Outlaw said.
Still, while officials this week are celebrating the identification of Joseph, the investigation into who was responsible for his death remains ongoing.
"We have our suspicions as to who may be responsible, but it would be irresponsible of me to share these suspicions as this remains an active and ongoing criminal investigation," said Capt. Jason Smith of the Philadelphia Police homicide unit. He hopes news of the ID prompts an "avalanche of tips from the public," but acknowledged the age of the case presents investigators with an "uphill battle."
"We may not make an arrest," Smith said. "We may never make an identification (of the killer). But we're going to do our darndest to try."
It was February 25, 1957, when Joseph's body was found in a box near Susquehanna Road, in a wooded area of northeast Philadelphia. It was clear then, Outlaw told reporters Thursday, that the child had "experienced horrors that no one, no one should ever be subjected to."
He had been "severely beaten," Smith added, and multiple bruises were visible on his body. His hair had been "crudely cut close to the scalp."
An autopsy confirmed the child was between the ages of 4 and 6 and found he "had sustained multiple abrasions, contusions, a subdural hemorrhage and pleural effusions," Smith said -- injuries that essentially amounted to blunt force trauma.
There was a great public interest in the case, and police received and followed up on hundreds of tips from the local area and across the country. "None, however, would lead them to the positive identification of the child," Smith said, adding it becomes extremely difficult to solve a homicide case and bring the killer to justice when the victim remains unidentified.
While DNA was discovered in the 1800s, DNA technology had not progressed far by the 1950s, Dr. Constance D'Angelo, the chief medical examiner, explained Thursday. Instead, "visual identification" was the principal method of identifying people, she said, and so authorities had photos of the child published in the newspaper, put posters up around the city and even included a photo with a gas bill sent out to residents.
Still, there was no breakthrough in the case.
The boy was originally buried in a potter's field in Philadelphia, where it lay until 1998 when his remains were exhumed before being subsequently reinterred at Ivy Hill Cemetery, where a headstone today reads, "America's Unknown Child."
Investigators retained portions of the child's remains for future testing, Smith said. But DNA tests at the time yielded no new leads.
Police exhumed the remains again in 2019 when it was determined the case could benefit from more modern forensic techniques, Smith said.
This time, the results of DNA testing were uploaded to DNA databases, Smith said. And with the help of genetic genealogists at Identifinders International, a forensic genetic genealogy company, detectives were able to locate and contact relatives in the child's maternal family.
Investigators identified the birth mother and obtained his birth records, which also listed the name of the father. Further research led detectives to an individual later confirmed through additional testing to be the child's father.
Police declined to identify the child's parents, but Smith said both are dead. However, Joseph has siblings who are still living.
Dr. Colleen Fitzpatrick, president of Identifinders International, said the case was the most challenging of her entire career, in part due to the extent that the DNA had degraded. But the discovery "means that we can pay it forward," she told CNN, "to identify so many other people that you think are lost for good, because you think the DNA is all chewed up, but maybe they aren't."
In the meantime, the Vidocq Society, a Philadelphia crime-solving club that has been among the case's champions over the years, is preparing to finally put a name on the grave of the child.
"Joseph Augustus Zarelli will no longer be that boy in the box," Bill Fletcher of the Vidocq Society said Thursday, "and will no longer be unknown."