A gold ring belonging to a World War II British pilot who died after his plane hit a mountain in Albania has been returned to his sister 55 years after the crash.

Flight Sgt. John Thompson began wearing the ring after he married Joyce Mozeley in June 1944. After spending just a weekend with his wife, he was stationed abroad to take part in sorties to assist Albanian rebels, Sky News reports.

On October 29, 1944, Thompson’s plane dropped supplies in Albania’s Biza valley, but clipped the top of a mountain while returning to Italy and crashed, killing the crew, said Gerd Kaceli, a military assistant at the British Embassy.

Thompson was never found and was presumed missing, but the ring was picked up by Albanian Jaho Cala in 1960 while he was collecting metal and wood in the mountains. The only clue as to who the ring belonged to were the words “Joyce & John” engraved on the inside.

He kept the ring and hid it at his home, afraid to show it to the then-Communist authorities.

The ring was later passed to Cala’s son, Xhemil.

"He gave it to me when I got married in 1971, but told me clearly the ring did not belong to our family and I was to return it to its owner after communism ended," Xhemil Cala told Sky News.

Albania was first occupied by Fascist Italy in 1939 and then by Nazi Germans in 1943. Led by the Communist Party, its partisans liberated the country on Nov. 29, 1944.

Two years ago, Xhemil Cala contacted the British embassy for help. Then in October 2014, a British-U.S. expedition found the remains of a Handley Page Halifax bomber 6,000 ft. up in Albania’s mountains.

After three months, the British Embassy confirmed the ring was Thompson's and told his family and the families of the other six crew members.

"The ring... really helped us to solve this riddle," said Chris Casey, who was part of the expedition.

Thompson’s widow remarried after the war and died in 1995, but his 92-year-old sister, Dorothy Webster, was given the ring on Monday, The Telegraph reports.

At a special ceremony at Albania's Defense Ministry, Xhemil Cala kneeled as he handed over the ring to Webster, along with a fuel gauge from the aircraft and a piece of rock from the mountain where it crashed.

Webster said she was "overwhelmed ... getting all these keepsakes that we never thought we would ever get,” according to Sky News.

"All these years it has been a story of loss," said one of her sons, Alan Webster. "We now know almost everything that happened. It's a sense of closure. We know where John is. He's over there in the mountain."

Alan's brother, Brian Webster, said their grandparents never locked their house in Matlock, Derbyshire County, in Britain because they were waiting for their missing son. British authorities never told them anything about Thompson because he was part of "a secret operation in Albania," the family said.

Defense Minister Mimi Kodheli said Thompson “will never be forgotten.”

"Your brother helped to liberate my country,” he said.

Xhemil Cala said he is relieved to have fulfilled his father's testament to return the ring to the owner's family.

"I will go to his grave and say rest in peace for your dying wish has been fulfilled," he said.

The Associated Press contributed to this report.

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