The documents, set to be released in a phased manner by UK-based independent journalist and Bose's grandnephew Ashis Ray, debunks the popular notion that Bose entered into Soviet Union in 1945, the year of his death as per records, and comes ahead of Prime Minister Narendra Modi's proposed visit to Moscow later this month.
It includes material Ray claims to have collected in Taiwan, Japan, Pakistan, the National Archives in Britain and the British Library, as well as from the Indian and Russian governments and some intelligence documents.
The first dated September 16, 1991, requests the Russian government to share "any material that sheds light on the fate of Netaji Subhash Chandra Bose".
The reply in January 1992 says that "according to the data in the Central and Republican Archives, no information whatsoever is available on the stay of the former President of the Indian National Congress, Netaji Subhash Chandra Bose, in the Soviet Union in 1945 and thereafter".
Following some "further speculation" in India on the matter, the Indian embassy made a second request for information in July 1995.
Commenting on the significance of documents released yesterday, Ray said: "The serialisation will emphatically prove what happened to Subhas Chandra Bose towards the end chart of his life hour by hour."
Ray said the documents will be published on a website to be launched soon.
There have been numerous conspiracy theories floated over the years on what really happened to Netaji, with claims that he survived a plane crash in Taiwan 1945.
In October, Modi had announced that the first batch of the secret files associated with the founder of the Indian National Army would be declassified from January 23, the birth anniversary of Netaji, meeting the long-pending demand of Bose's family.
