Aviation pioneer Amelia Earhart and her navigator were executed by the Japanese government to avoid an international incident, and the US played along, a shocking theory claims.

The theory says Earhart, who was the first female aviator to fly solo across the Atlantic Ocean, and navigator Fred Noonan were killed on the island of Saipan, now a US commonwealth, after their disappearance in 1937 has been around for more than 50 years now.

But now claims have emerged that Earhart's body was retrieved by the US military - which may have hidden her killing to keep the peace, the Pacific Daily News reported.

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Did Amelia Earhart and navigator Fred Noonan (both pictured) die at the hands of Japanese soldiers, not exposure, after their disappearance in 1937? New evidence backs that claim

Bill Sablan of Guam says his uncle worked in a prison camp on the island of Saipan in the late '30s when two American pilots - one female - were brought in, having been found at sea

Saipan prison camp where Bill Sablan of Guam says his uncle worked is pictured

The theory fits the recollections of William 'Bill' Sablan, a resident of Guam whose uncle, Tun Akin Tuho, worked at the Saipan prison camp.

Sablan, who was born in Guam and raised in San Diego, told the Daily News that he remembered telling Tun in 1971 about how he hoped to become a pilot.

That triggered a memory in Tun, who recalled how two white pilots had been interned for several days on Saipan, then a Japanese hub, before they were executed.

He said his uncle couldn't recall the exact date, but said that 'some time in the middle '30s' an American woman and man were brought in for questioning.

That was unusual, and caused an uproar in the otherwise quiet prison, Tun had said.

They had been found in the southern islands, Tun told Saipan, and Japan had ordered them to be brought in.

'But during their session, I guess, Imperial Japan didn't want anything to do with them, because hey didn't want to get involved in any national [sic] scandal,' Sablan said.

Sablan said his uncle claimed Imperial Japan decided to kill the pair because they wanted to avoid an incident, and that the US military collected their bodies after World War II

'So apparently I think they were both killed in Saipan and buried there, and I found out later on as I made my inquiries that... after the war was over, their bodies were exhumed by an American military branch and shipped back to the United States.

'Now where those bodies are now is somebody's own question to answer.'

The Daily News suggested that they may have kept quiet in order to avoid an incident of their own.

That contradicts the most popular theory, which is that she crashed and died in the sea on July 2, 1937, after noting poor visibility and her declining gas levels in a series of transmissions earlier that morning.

But it fits a theory proposed on the History Channel special Amelia Earhart: The Lost Evidence in July that Earthart died at the hands of the Japanese, and that her murder was covered up by the US government.

Sablan's story is the latest in a number of pieces of evidence that suggest Earhart died on Saipan, rather than perishing at sea.

That theory emerged in 1960, when CBS radio reporter Fred Goerner interviewed several witnesses who said that two white 'flyers' or 'spies' had been picked up on the island before the Second World War.

They claimed that one of them was a tall white woman with short hair, dressed like a man.

His claim fits a long-standing theory that Earhart died on Saipan, even though the most common belief is that she and Noonan died after ditching at sea

Josephine Blanco Akiyama (left) was 12 years old and living in Saipan (right) when she claims to have seen Earhart being hauled away by the Japanese in July 1937 after crashing her plane

And in July, Josephine Blanco Akiyama, who grew up on Saipan but now lives in California, said she saw the pair as a child.

'I didn't even know it's a woman, I thought it's a man,' Akiyama told NBC's Today that month.

'Everybody was talking about her but they were talking in Japanese - that's why I know that she's a woman. They were talking about a woman flyer.'

Akiyama, who was 12 at the time, claims she later learned Earhart had been executed.

Also in July, a fuzzy photograph emerged as part of the promotion for the History Channel documentary purporting to show Earhart and Noonan in Saipan, along with her plane, in 1937.

It shows a woman - purportedly Earhart - facing away from the camera. A man who is said to be Noonan stands nearby, while her crippled plane can be seen on the far right being dragged by a large ship.

The faces of the two cannot be seen, but their profiles do bear a striking similarity to the pair. It has been claimed that the photographer was a US spy or emissary operating behind enemy lines in the Pacific.

A facial recognition expert said that it is likely Earhart and Noonan in the photo, which was discovered in the National Archive by retired federal agent Les Kinney.

This image reportedly shows Amelia Earhart (sitting center) after she vanished from the sky - but it is disputed by some. It was found in the national archive

Experts disagree on whether the figures are indeed Noonan and Earhart. It's also been asked why the photo, purportedly taken in 1937, was found with photos taken in 1940

But investigators told MailOnline a year ago that the photo could not be that of Earhart because it was found among a batch of pictures taken after 1940 - three years after Earhart vanished.

An investigator who researched the photo for MailOnline believed initially that the figures on the end of the jetty showed Earhart and Noonan but his enthusiasm waned when he realized the date they were supposedly taken.

'The 1940+ date is probably the most disheartening of all,' the investigator said, adding that the body shapes of 'Earhart' and 'Noonan' did not appear to be correct.

And another recognized Earhart investigator, Mike Campbell, has lashed out at what he described as 'bogus photo claims'.

Campbell said it wasn't evidence of anything except that a Japanese ship, the Koshu Maru, was once in Jaluit Harbour.

Campbell claims that the photo 'does little except discredit the truth'.

He says that Earhart and Noonan are 'absolutely not in the photo and it's incredible that anyone could believe they are'.

'Zoom in and you can see the upper half of a white man with black hair on the far left of the group on the dock,' he said, but adds that the features, the nose, the hairline are all wrong 'and any intelligent analysis rules him out'.

The alleged details of Earhart's final flight, and where she is believed to have ended up based on different theories over the years

Campbell said that 'nobody in the photo remotely resembles Earhart inasmuch as anyone's facial features can be determined at all'.

MailOnline's investigation last year also concluded that if Earhart and Noonan had been captured by the Japanese, the suspected spies would have been under guard but there is no sign of any Japanese soldier on the jetty.

'The group on the dock appears to be out for a Sunday stroll, or awaiting someone's arrival from one of the ships in the harbour,' Campbell said.

As the MailOnline's investigator who uncovered the questionable photo notes: 'In the archives I found that the envelopes containing the photographs were stamped on the lower rear corner - something that was difficult to notice as they're in a three-ring binder/enclosure.

'The [aerial] surveillance photos in the first few envelopes were dated earlier than the 1940s, but the photos taken from on the island [Jaluit], that were in the latter envelopes, were dated 1940+'.