Imphal, 28 June 2016 ( Evening News) : Isak Chisi Swu, co-founder of the National Socialist Council of Nagaland-Isak-Muivah (NSCN-IM), died today at Fortis Hospital, New Delhi. He was 87. Isak was admitted to the Fortis Hospital in south Delhi on July 5 last year following "severe kidney ailments and urinary tract infection". He died at the Fortis Hospital, Vasant Kunj this afternoon at 12.40. He joined the underground movement in the late 1950’s and served as foreign secretary of Naga National Council which was the political organisation of the Naga people. Under the leadership of Angami Zapu Phizo in 1940s, he unsuccessfully campaigned for secession of the Naga territory from India and creation of a Sovereign Naga State. Isak Chisi Swu, Thuingaleng  Muivah and SS Khaplang formed the National Socialist Council Of Nagaland on January 31, 1980. NSCN was formed opposing the Shillong Accord signed by then Naga National Council and the Government of India. Following the disagreement the group split into two factions, NSCN-K led by SS Khaplang and NSCN-IM led by Isak Chisi Swu and Thuingaleng  Muivah.