NEW DELHI: India's government on Saturday started declassifying secret files to settle questions over the death of Subhash Chandra Bose, a Congress party leader who formed a national army to fight British colonial rulers with the help of the Japanese in the 1940s.

Prime Minister Narendra Modi released digital copies of 100 secret files relating to Bose's life in the presence of several members of his family. The National Archives of India plans to release digital copies of 25 declassified files on Bose every month.

India's Civil Aviation Mnister Mahesh Sharma said Modi already has informed Bose's family that the government possessed "only circumstantial evidence and not any direct evidence about his death."

Bose advocated an armed struggle for Indian independence against British colonialists. He led the radical wing of the Congress party in late 1920s and 1930s. He later became the Congress party president but quit the post following differences with Mohandas K. Gandhi who believed in a non-violent struggle against the British.

Bose left India in 1940. After the country gained independence from Britain in 1947, two commissions of inquiry concluded Bose died in a plane crash in 1945 in Taipei, Taiwan.

A third concluded that he did not die in the reported crash, but it did not address the possibility he went to the then-Soviet Union. That commission called for further investigation but also presumed him to be dead at the time of the inquiry, which was released in 2006.

The Modi government has asked Moscow to provide any evidence it has in its possession.

The Bose family didn't believe in the plane crash conclusion and sought declassification of government files.

Chandra Kumar Bose, a member of the Bose family at the ceremony, said: "We welcome this step by the prime minister wholeheartedly. This is a day of transparency in India."