A Canadian documentarian says in a new film that an elderly man he found living in a remote Vietnamese village is former U.S. Army Green Beret Sgt. John Hartley Robertson, who was presumed dead 44 years ago. According to The Independent, filmmaker Michael Jorgensen claims that the man found in a village in South Vietnam can't remember the English language or the names of his wife and children, but that he is the U.S. veteran whose helicopter was shot down in 1968.

"Unclaimed" is set to premiere Tuesday at the Toronto Film Festival. It details the search by U.S. Vietnam veteran Tom Faunce to locate and identify Robertson, who was flying a top secret mission to Laos when his helicopter went down. Robertson's family tried for years to establish that he was alive or at least find his remains, but to no avail.

Faunce was traveling in Vietnam in 2008 when he heard a rumor of an "Army brother" who had been shot down some 40 years before, listed as killed in action and forgotten by his country. Eager to make good on his military vow to never leave any soldier behind, Faunce embarked on a mission to find the purported veteran and reunite him with his U.S. family or reveal his story to be a hoax.

Jorgensen said he was skeptical at the outset of the project.

“The MIA story was pretty unbelievable, pretty grandiose," Jorgensen told the Globe and Mail. “Tom went to meet him and was very skeptical, grilling this guy up and down, trying to get him to break."

Through an interpreter, the elderly man said that he was captured by North Vietnamese troops shortly after his helicopter crashed. He claimed that he was kept in a bamboo cage and tortured for a year. As Faunce and Jorgensen got to know the man, they became more convinced that he was Robertson.

A combination of age and possible head trauma in the crash have left the man claiming to be Robertson confused and suffering from possible dementia. He said that eventually he was released by his captors when they took pity on the state of his injuries. A local nurse cared for him and eventually the two fell in love and were married.

The documentary includes reunions between Robertson and his surviving relatives back in the U.S. like 80-year-old sister Jean Robertson Holly, who was overjoyed to see her brother again.

“There’s no question," said Robertson Holly. "I was certain it was him in the video, but when I held his head in my hands and looked in his eyes, there was no question that was my brother.”

She declined to have the man she believes to be her brother's identity verified by DNA testing, saying that she didn't feel that it was necessary.

UPDATE: The man claiming to be John Hartley Robertson has been exposed as a fraud. According to the Independent, the impostor's story was "shattered" Wednesday, when a 2009 memo surfaced from the Defense Prisoner of War Missing Personnel Office saying "that the found man was in fact a fraudster who the US government performed DNA tests on 20 years ago and whose story had been fully debunked as an attempt to exploit Vietnam’s Missing in Action and Prisoner of War groups and claim military back-pay."

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