New Delhi: The Narendra Modi government is set to launch its first major initiative to fulfil its election promise of sending back illegal Bangladeshi migrants. The issue was repeatedly flagged by Mr Modi during his election rallies in West Bengal and other states. For the first time in 50 years, a mammoth exercise will be undertaken to identify all illegal Bangladeshi migrants settled in Assam after 1971. The National Register of Citizens (NRC), 1951, in Assam will be the benchmark and will be updated with the 1971 electoral rolls. Incidentally, the exercise was abandoned by the UPA government in 2010 even before it could be rolled out after it developed cold feet fearing a communal backlash.