(RNN) – Investigators with a new History Channel documentary believe a photograph discovered in a former "top secret" file at the National Archives may hold clues to what happened to Amelia Earhart.
Taken in 1937, the photograph shows a woman sitting on a dock in the Marshall Islands, along with a Caucasian man standing near a pole. Earhart traveled with navigator Fred Noonan.
The famed pilot disappeared July 2, 1937, over the Pacific Ocean as she and Noonan attempted to fly around the world.
Retired U.S. Treasury Department investigator Les Kinney found the photograph stamped with an official Office of Naval Intelligence markings that read Jaluit Atoll in the Marshall Islands.
The islands were under Japanese Control at the time, and the investigators said the person who took the photograph was later executed for being a spy.
A Japanese military ship towing a barge with something that appears to be the same length as Earhart's plane is also seen in the photograph.
Kinney says the photograph had to have been taken before 1943 because the U.S. bombed the area multiple times from 1943-1944.
The group claims Earhart and Noonan were taken to Saipan, where they died. For years, the Japanese Military has denied they knew what happened to Earhart.
However, documents from that time were destroyed in World War II, and no officials who lived then are alive now.
The History Channel will broadcast "Amelia Earhart: The Lost Evidence" at 9 p.m. ET on Sunday.