'When any person accused of the commission of any offence relating to Schedule I or Part II of Schedule II or offences relating to hunting inside the boundaries of National Park or Wildlife Sanctuary or altering the boundaries of such parks and sanctuaries, is arrested under the provisions of the Act, then not withstanding anything contained in the Code of Criminal Procedure, 1973, no such person who had been previously convicted of an offence under this Act shall be released on bail unless -