In 1940, a few Sikhs such as the victims of Komagata Maru in Canada proposed the idea of Khalistan as a buffer state between an independent India and what would become Pakistan. These leaders, however, were largely ignored. The early 1980s witnessed some Sikh groups seeking an independent nation named Khalistan carved out from India and Pakistan. The Golden Temple and Akal Takht were occupied by various militant groups in 1982. These included the Dharam Yudh Morcha led by Jarnail Singh Bhindranwale, the Babbar Khalsa, the AISSF and the National Council of Khalistan. Between 1982 and 1983, there were Anandpur Resolution demand-related terrorist attacks against civilians in parts of India. By late 1983, the Bhindranwale led group had begun to build bunkers and observations posts in and around the Golden Temple, with militants involved in weapons training. In June 1984, the then Prime Minister of India Indira Gandhi ordered Indian Army to begin Operation Blue Star against the militants. The fierce engagement took place in the precincts of Darbar Sahib and resulted in many deaths, including Bhindranwale, the destruction of the Sikh Reference Library, which was considered a national treasure that contained over a thousand rare manuscripts, and destroyed Akal Takht. Numerous soldiers, civilians and militants died in the cross fire. Within days of the Operation Bluestar, some 2,000 Sikh soldiers in India mutinied and attempted to reach Amritsar to liberate the Golden Temple. Within six months, on 31 October 1984, Indira Gandhi's Sikh bodyguards Satwant and Beant Singh assassinated her. The assassination triggered the 1984 anti-Sikh riots. According to Donald Horowitz, while anti-Sikh riots led to much damage and deaths, many serious provocations by militants also failed to trigger ethnic violence in many cases throughout the 1980s. The Sikhs and their neighbors, for most part, ignored attempts to provoke riots and communal strife.