arrest

Every police officer while making an arrest shall— (a) bear an accurate, visible and clear identification of his name which will facilitate easy identification. [S.41B (a) of Code, 1973]

A police officer making an arrest without warrant shall, without unnecessary delay and subject to the provisions herein contained as to bail, take or send the person arrested before a Magistrate having jurisdiction in the case, or before the officer in charge of a police station. [S.56 of Code, 1973] 

Whenever any person is arrested and detained in custody, and it appears that the investigation cannot be completed within the period of twenty-four hours fixed by section 57, and there are grounds for believing that the accusation or information is wellfounded, 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. [S.167 (1) of Code, 1973] 

The Magistrate to whom an accused person is forwarded under this section may, whether he has or has not jurisdiction to try the case, from time to time, authorise the detention of the accused in such custody as such Magistrate thinks fit, for a term not exceeding fifteen days in the whole. [S.167 (2) of Code, 1973]

On a reading of the sub-sections (1) and (2) of S.167 it may be seen that sub-section (1) is a mandatory provision governing what a police officer should do when a person is arrested and detained in custody and it appears that the investigation cannot be completed within the period of 24 hours fixed by Section 57 of Code, 1973. Since sub-section (1) of S.167 of Code, 1973 provides that if that investigation cannot be completed within the period of 24 hours fixed by S.57 the accused has to be forwarded to the Magistrate along with the entries in the Diary, it follows that a police officer is entitled to keep an arrested person in custody for a maximum period of 24 hours for purposes of investigation. Refer Chaganti Satyanarayan v. State of AP [1986] GCtR 6080(SC).