(1)A person shall not be proceeded against for any offence under section 24 or section 25 or section 26 or for any offence under the Indian Penal Code, except with the previous sanction of the Commissioner or Commissioner (Appeals):Provided that the Chief Commissioner or, as the case may be, Director General may issue such instructions or directions to the aforesaid interest-tax authorities as he may deem fit for institution of proceedings under this sub-section.