A History Channel documentary that claimed pioneering aviator Amelia Earhart crash-landed in the Marshall Islands during her 1937 attempted round-the-globe flight and was taken prisoner by the Japanese military appears to have been disproved, the Guardian reported Tuesday.

A story published by the British media company said a Tokyo-based blogger found the photograph on which the documentary’s claims were based in the archives of the National Diet Library, Japan’s national library. The image was part of a Japanese-language travelogue about the South Seas that was published in 1935 — almost two years before Earhart disappeared, the story said.

Without referring specifically to the Guardian’s story, the History Channel said in a tweet Tuesday morning that it has a team of investigators exploring the latest developments about Earhart and that it would be transparent about its findings.

The photo in question shows a group of people on a dock, one of whom appears to be a woman sitting with her back to the camera. The History Channel documentary, “Amelia Earhart: The Lost Evidence,” which aired Sunday night, claimed the photo showed Earhart and navigator Fred Noonan alive and well after their disappearance en route to Howland Island. The film used facial recognition and other forensic testing to support the claim.

Former U.S. Treasury Agent Les Kinney told The Associated Press last week he found the photo at the National Archives in a batch of documents collected by U.S. sources in anticipation of the 1944 invasion of the Marshall Islands.

Kota Yamano, a military history blogger who unearthed the Japanese photo, said it took him just 30 minutes to effectively debunk the documentary’s central claim, according to the Guardian.

“I have never believed the theory that Earhart was captured by the Japanese military, so I decided to find out for myself,” Yamano told the Guardian. “I was sure that the same photo must be on record in Japan.”

Yamano ran an online search using the keyword “Jaluit atoll” and a decadelong time frame starting in 1930.

“The photo was the 10th item that came up,” he said. “I was really happy when I saw it. I find it strange that the documentary makers didn’t confirm the date of the photograph or the publication in which it originally appeared. That’s the first thing they should have done.”

The documentary, hosted by former FBI executive assistant director Shawn Henry, also alleged a cover-up, claiming the U.S. government knew of her whereabouts but did nothing to rescue her.

In Earhart’s hometown of Atchison last week, several people expressed a keen interest in the photo and documentary.

July 2 marked the 80th anniversary of Earhart’s disappearance.