If the investigation is not completed in 24 hours?

CrPC Section167. Procedure when investigation cannot be completed in twenty-four hours—(1) Whenever any person is arrested and detained in custody, and it appears that the investigation cannot  completed within the period of twenty-four hours fixed by section 57, and there are grounds for believing that the accusation or information is well-founded, the officer in charge of the police station or the police officer making the investigation, if he is not below the rank of sub-inspector, shall forthwith transmit to the nearest Judicial Magistrate a copy of the entries in the diary hereinafter prescribed relating to the case, and shall at the same time forward the accused to such Magistrate.