Some Earhart researchers believe that Fred and Amelia landed at, or ditched near Mili Island in the Pacific north west of Howland Island. Mili was also known as Mille, Miri, and Mulgrave Island. In 1937, Mili was one of the many Marshall Islands under Japanese administration, by League of Nations Mandate.
Some believe that Fred and Amelia (perhaps along with their plane and/or equipment) were captured by the Japanese on Mili and transported to Jaluit Island, and from there, sent to be imprisoned on Saipan where they died or were executed as spies by the Japanese.
Most of the evidence supporting this theory comes from testimony of islanders and US service men who claim to have seen or known of an American woman prisoner of the Japanese. Some said that they heard she and/or a man with her were aviators. Stories vary.
The reasons given for Amelia possibly being in the area of the Marshall Islands were that she was on a secret mission to photograph and report on Japanese military build up of the islands in violation of the League of Nations Mandate.
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Mili Island (Mille)
Marshall Islands

7th AF c1944

USN 1944
Location
Lat 6° 7' 60N Long 171° 55' 0E Mili Island is located at the southwest edge of
Mili Atoll (Mille) in the
Marshall Islands. Also known as "Mille Island". Borders the lagoon to the east. To the southeast is Arbar Island and Madagai Island to the north...
After World War I, Pacific Islands previously claimed by Germany were administered as part of the South Pacific Mandate by
Japan. These were referred to as "The Mandated Islands" or "The Mandates".
Wartime History
Mili Island was small lookout post, radio direction finding station and weather station. During late 1942, the Japanese began developing an airfield on the island, using Korean and Marshallese labor force. At its height, the garrison included 5,100 Japanese including 2,600 Navy and 2,500 Army. The base lacked any large concrete structures, such as command buildings, power stations or bunkers. The island had one radar with a range of 50 miles, giving ten minutes warning for any enemy aircraft inbound...
... By late 1943, supply lines to Mili were cut off, and the Japanese garrison was left to starve. Over eighteen months, Mili was the target of US aircraft. The garrison of 5,100 Japanese (2,600 Navy and 2,500 Army,) only 2,500 (50%) survived. Casualties occurred from air raids, diseases, accidents, and suicides, but mainly from starvation.
American missions against Mili Island
June 17, 1943 - August 30, 1944
On August 22, 1945, the Japanese garrison on Mili was the first Pacific island to surrender, eleven days before the formal surrender of Japan.
Mili Airfield
Built by the Japanese, still in use today for local air service...
Source:
Pacific Wrecks - Mili Island (Mille) Marshall Islands