The Bengali Language Movement of Barak Valley was a protest against the decision of the Government of Assam to make Assamese the only sole official language of the state, even though knowing that a major proportion of the Barak Valley population speaks Bangla language. About 80% of the Valley's residents are ethnic Bengalis. In the Barak Valley region, the ethnic Bengali population consists of both Hindus and Muslims, who are almost equal in population and constitute the overwhelming majority of the population. There is also a substainable minority of native tribals and immigrants from other parts of India. The main incident took place on 19 May 1961 at Silchar railway station in which 11 ethnic Bengalis were killed by Assam police.