Interest on delayed customs duty applied to special cases of short levy, suppression, and erroneous refund under the omitted provision. Interest on delayed payment of customs duty in special cases applied where duty was not levied, not paid, short-levied, short-paid, or erroneously refunded, including cases of collusion, wilful misstatement, or suppression of facts. Interest was payable in addition to duty from the relevant due date or refund date until payment, subject to a Central Government notified rate. A special rule exempted voluntary payment within forty-five days of a Board order without appeal rights, and appellate reduction or increase of duty altered the amount on which interest was payable. The section was later omitted.