A Green Beret reported killed during the Vietnam War may have been found alive 44 years later

U.S. Army Master Sergeant John Hartley Robertson, a Green Beret, was in a helicopter shot down over Laos in 1968. His body was never found and was presumed dead. His name is on the Vietnam War Memorial in Washington, D.C. and the Army officially lists him as Killed In Action.

In 2013, a fellow vet named Tom Faunce claimed to have traced the men killed in the crash to those taken prisoner by the North Vietnamese Army around the same time. The men were taken prisoner and tortured, but Faunce claims the men all survived. The claims sparked renewed interest in finding and repatriating possible POWs remaining in Vietnam for so long after the war.

In a documentary film called Unclaimed, Faunce teamed up with Emmy-winning director Michael Jorgenson to find a man they thought to be Robertson, then 76-years old, 44 years after the crash. The missing Green Beret was supposedly living in a village of south-central Vietnam. The man had no memory of being Robertson, had no memory of his children, his own birthday, or even the English language.

Master Sgt. Robertson's family believed he could have survived the event and even claimed to have supporting documentation that he had been held in an NVA prison. Jorgenson maintained the U.S. government has had proof of Robertson's survival since 1982, but did not do anything with the information.

Still, the filmmaker was skeptical and went to Vietnam with Faunce believing they would uncover a hoax. The man who would be Robertson, now calling himself Dan Tan Ngoc, said he was held, beaten, and tortured but eventually released into t he care of a local nurse, whom he married and with whom he later had children.

The Army fingerprinted Dan Tan Ngoc at a U.S. Embassy, but said it was not enough to prove Dan Tan Ngoc was indeed John Hartley Robertson. The film shows a reunion of the man who would be Robertson meeting a fellow vet he trained and Robertson's own sister, Jean, who said "There's no question. 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."

Except, he may not be.

In 2014, DNA testing proved Dan Tan Ngoc could not be John Hartley Robertson. Robertson's niece, Cyndi Hanna, called the result "very disappointing." Yet, the Robertson family still believes Ngoc is their missing loved one. Gail Metcalf, daughter of Robertson's sister, Jean bases this on a oxygen isotope analysis performed on the man's tooth. The family set up a Go Fund Me page to help raise money for DNA testing and Master Sgt. Robertson's repatriation. Salt Lake City's IsoForensics Inc., performed the test for the filmmakers and came to the conclusion  it is "very likely" Ngoc grew up in U.S., a result the family takes to heart.

"We only want to do right by my Uncle John," Metcalf told Stars and Stripes. "If that means exploring the possibility that the U.S. government has made a mistake or that the man claiming to be my uncle is actually another lost American and doesn't know who he is, we intend to seek the truth on our own terms."