The Bodoland movement was mainly led by the political organisations All Bodo Students Union (ABSU) and Bodo Peoples' Action Committee (BPAC). In 1993, these two groups signed the Bodo Accord with Indian government, agreeing to the formation of Bodoland Autonomous Council within Assam. BdSF opposed this Accord. Shortly after the Accord, the Assam State Government refused to hand over 2,750 villages to the proposed Council, arguing that Bodos formed less than 50% of the population in these villages. Following this, the BdSF was renamed to National Democratic Front of Bodoland (NDFB) on 25 November 1994. The NDFB then launched an ethnic cleansing campaign, attacking non-Bodo communities in these villages. During the 1996 Assam Legislative Assembly elections, it killed hundreds of Santhal, Munda and Oraon adivasis (tribals), whose ancestors had been brought to Assam as tea labourers during British Raj. In response, the tribals formed Adivasi Cobra Force, their own militant group.