"After 1971, East Bengal made a fresh start as a secular state, and many refugees returned in the hope of a decent life. But soon Islamization policies returned to the country, along with discriminations and pogroms against the minorities. Consequently, Hindus as well as Christians and Buddhists from Bangladesh have gradually moved to India. This picture is muddied a bit by the seemingly parallel but actually quite distinct phenomenon of mass Muslim emigration from Bangladesh to India for purely economic reasons. Estimates approved by the Indian government put the number of Bangladeshi Muslims illegally staying in India at over 20 million. Most border regions of West Bengal and the North-Eastern states, originally allotted to India rather than to East Pakistan precisely because they had Hindu majorities, now have large Muslim majorities. Hindus are under pressure to leave there, too. [...] But meanwhile, the stark fact is that the continuous trickle of Hindu refugees from Pakistan and Bangladesh is not reciprocated by a symmetrical phenomenon of Muslim flight from India. On the contrary, even in BJP-ruled India, even in Mumbai a.k.a. Shiv Sena City, there is a continuous influx of Bangladeshi Muslim fortune-seekers. They vote with their feet to refute Mira Kamdar's alarmist stories."
January 1, 1970
https://en.wikiquote.org/wiki/Religion_in_Bangladesh