Section 402(1) in The Calcutta Municipal Corporation Act, 1980
(1)The Municipal Commissioner may, at any time during the erection of any building or the execution of any work or at any time within three months after the completion thereof, by a written notice, specify any matter in respect of which such erection or execution is without or contrary to the sanction referred to in section 396 or is in contravention of any condition of such sanction or of the provisions of this Act or the rules or the regulations made thereunder and require the person who gave the notice under section 393 or section 394 or the owner of such building or work either-(a)to make such alterations as may be specified by the Municipal Commissioner in the notice with the object of bringing the building or the work in conformity with such sanction or such condition of such sanction or such provisions of this Act or the rules or the regulations made thereunder, or(b)to show cause, within such period as may be stated in the notice, why such alterations should not be made.
