The officials of Assam Plains Tribes Development Authority (APTDA) had siphoned off Rs 2.75 crore during April 1, 1993 to April 30, 1996 in the name of supply of teaching-aid material to various schools, clubs , cooperative bodies etc, in plains tribes areas, when they "paid" the money to two supplier-contractors of the city, even though the total budgetary allocation was only Rs 1.50 crore for the purpose.