In 1950 , it is estimated that a further one million refugees crossed into West Bengal , particularly in the aftermath of 1950 Barisal riots and Noakhali riots . The 1951 Census of India recorded that 27 % of Kolkata 's population was East Bengali refugees mainly Hindu Bengalis and they contributed the economic growth of Kolkata in various fields . Millions of Hindus particularly Bengali speaking from East Pakistan took refuge mainly in India 's various state . A number estimated that around 3.2 lakhs Hindus from East Pakistan migrated mainly to Kolkata and various rural areas and towns of West Bengal during 1947
Noakhali riots
Noakhali riots
East Bengali refugees