Birpara, Dec 27 (ANI): Several tribal groups on Saturday have called for shutdown in Birpara area of Alipurduar district of West Bengal following the attacks by the National Democratic Front of Bodoland (NDFB) which killed over 80 people. NDFB militants killed over 80 people in the Sonitpur, Kokrajhar and Chirang districts of Assam ths week. Various groups such as All Assam Tea Tribes Student Association, Adivasi Chhatra Sangathan, Akhil Assam Bhojpuri Parishad, All Assam Minority Students' Union (AAMSU) and seven other groups had observed Bandh in several areas of Assam even on Friday.