(1) If upon information which has come into his possession, the prescribed authority is satisfied that reasonable grounds exist to believe that any dealer has been liable to pay tax under this Act in respect of any period, and has nevertheless wilfully failed to apply for grant of certificate of registration, or, having so applied, failed to furnish any particulars or information required for the purposes of section 19, the prescribed authority shall, after giving the dealer a reasonable opportunity of being heard, assess, to the best of its judgment, the amount of tax due, if any, from the dealer in respect of such period and all subsequent periods; and the prescribed authority may, direct that the dealer shall pay, by way of penalty, in addition to the amount of tax so assessed, a sum of one hundred rupees for every day of the period during which the dealer failed to apply for registration or failed to furnish any particulars or information required for the purposes of section 19 or an amount equal to the amount of tax assessed, whichever is higher:
     Provided that no proceeding for such assessment shall be initiated except before the expiry of two years from the expiry of the period to which it relates:
    Provided further that a proceeding initiated under this sub-section shall be completed within a period of four years from the date of initiation.
     (2) Any assessment made, interest levied or penalty imposed under this section shall be without prejudice to any action which is, or may be, taken under section 81.