Section 400(7) in Kolkata Municipal Corporation Act, 1980
(7)where no appeal has been preferred against an order made by the Municipal Commissioner under Subsection (1) or where an order under that subsection has been confirmed on, whether with or without modification, the person against whom the order has been made shall comply with the order within the period specified therein, or as the case may be within the period, if any fixed by the Municipal Building Tribunal on appeal, and on the failure of such person to comply with the order within such period, the Municipal Commissioner may himself cause the building or the work to which the order relates to be demolished and the expenses of such demolition shall be recoverable form such person as an arrear of tax under this Act.
