A man who was abducted as a six-year-old while playing in a California park in 1951 has been found more than seven decades later thanks to the help of an online ancestry test, old photos and newspaper clippings.

The Bay Area News Group reported on Friday that Luis Armando Albino’s niece in Oakland – with assistance from police, the FBI and the justice department – located her uncle living on the US east coast.

Albino, a father and grandfather, is a retired firefighter and Marine Corps veteran who served in Vietnam, according to his niece, 63-year-old Alida Alequin. She found Albino and reunited him with his California family in June.

On 21 February 1951 a woman lured the six-year-old Albino from the park in West Oakland, where he had been playing with his older brother, and promised him in Spanish that she would buy him candy.

Instead, the woman kidnapped the Puerto Rico-born boy, flying him to the east coast, where he ended up with a couple who raised him as if he were their own son, the news group reported. Officials and family members didn’t say where on the east coast he lives.

For more than 70 years, Albino remained missing but he was always in the hearts of his family and his photo hung at relatives’ houses, his niece said. His mother died in 2005 but never gave up hope that her son was alive.

Oakland police acknowledged that Alequin’s efforts “played an integral role in finding her uncle” and that “the outcome of this story is what we strive for”.

In an interview with the news group, she said her uncle “hugged me and said ‘Thank you for finding me’ and gave me a kiss on the cheek”.

Oakland Tribune articles from the time reported that police, soldiers from a local army base, the Coast Guard and other city employees joined a huge search for the missing boy. San Francisco Bay and other waterways were also searched, according to the articles. His brother, Roger Albino, was interrogated several times by investigators but stood by his story about a woman with a bandana around her head taking his brother.

The first notion that her uncle might be still alive came in 2020 when, “just for fun”, Alequin said, she took an online DNA test. It showed a 22% match with a man who eventually turned out to be her uncle. A further search at the time yielded no answers or any response from him, she said.

Early this year, she and her daughters began searching again. On a visit to the Oakland public library she looked at microfilm of Tribune articles – including one that had a picture of Luis and Roger – which convinced her that she was on the right track. She went to Oakland police the same day.

Investigators eventually agreed the new lead was substantial, and a new missing persons case was opened. Oakland police said last week that the missing persons case was closed, but they and the FBI considered the kidnapping investigation to still be open.

Luis was located on the east coast and provided a DNA sample, as did his sister, Alequin’s mother.

On 20 June, investigators went to her mother’s home, Alequin said, and told them both that her uncle had been found.

“We didn’t start crying until after the investigators left,” Alequin said. “I grabbed my mom’s hands and said, ‘We found him.’ I was ecstatic.”

On 24 June, with the assistance of the FBI, Luis came to Oakland with members of his family and met with Alequin, her mother and other relatives. The next day Alequin drove her mother and her newfound uncle to Roger’s home in Stanislaus County, California.

“They grabbed each other and had a really tight, long hug. They sat down and just talked,” she said, discussing the day of the kidnapping, their military service and more.

Luis returned to the east coast but came back again in July for a three-week visit. It was the last time he saw Roger, who died in August.

Alequin said her uncle did not want to talk to the media.

“I was always determined to find him, and who knows, with my story out there, it could help other families going through the same thing,” Alequin said. “I would say: don’t give up.”