Cognizability of service tax offences enables arrest by authorised central excise officers, subject to CrPC arrest and bail safeguards. Sections 90 and 91, inserted into the Finance Act, 1994, classify clause (ii) offences under section 89(1) as cognizable and render other offences non-cognizable and bailable. The Commissioner may authorise Central Excise officers (not below Superintendent) to arrest persons reasonably believed to have committed offences under clause (i) or (ii). Arrests for cognizable offences must follow CrPC safeguards, including informing grounds of arrest and production before a magistrate within twenty-four hours, while Assistant and Deputy Commissioners have bail powers equivalent to an officer in charge under section 436 CrPC for non-cognizable bailable offences.