Registration of FIR in cognisable offence is a must and action must be taken against police officials for not lodging a case in such offences, the Supreme Court today held.br br A five-judge Constitution Bench headed by Chief Justice P Sathasivam said, "We hold registration of FIR is mandatory and no preliminary enquiry is permissible in cognisable offences."br br The bench, also comprising justices B S Chauhan, Ranjan P Desai, Ranjan Gogoi and S A Bobde, said action must be taken against erring police officials for not registering FIR in cognisable offences.