New Delhi, Dec 7 : The Supreme Court on Thursday asked the Union government to inform it about the administrative steps taken to prevent the inflow of illegal immigrants into Indian territories from northeastern states, particularly from Assam. A Constitution Bench, headed by CJI D.Y. Chandrachud also asked the Centre to submit details regarding border fencing and estimated timelines to complete the fencing exercise. The 5-judge bench, also comprising Justices Surya Kant, M.M. Sundresh, J.B. Pardiwala, and Manoj Misra, asked about the number of Bangladeshi immigrants granted citizenship in Assam between January 1, 1966 and March 25, 1971 under section 6A (2)of the Citizenship Act, 1955. It also sought to know the number of foreigners detected under the Foreigners Tribunals Order during the above period and called for an estimated inflow of illegal migrants into India, including Assam, after March 25, 1971. The top court asked the Union and Assam governments to file a common affidavit on or before Monday. The Constitution Bench is hearing a batch of challenging the constitutional validity of Section 6A of the Citizenship Act, 1955. The petitions against Section 6A primarily challenge provisions of the Assam Accord which formed the basis of the National Register of Citizens (NRC) in Assam, published in 2019. /IANS