Explanation:

Section 41, 43 and 44 of Code of Criminal Procedure – 
41. When police may arrest without warrant.—(1) Any police officer may without an order from a Magistrate and without a warrant, arrest any person— 1 [(a) who commits, in the presence of a police officer, a cognizable offence; (b) against whom a reasonable complaint has been made, or credible information has been received, or a reasonable suspicion exists that he has committed a cognizable offence punishable with imprisonment for a term which may be less than seven years or which may extend to seven years whether with or without fine, if the following conditions are satisfied, namely:— (i) the police officer has reason to believe on the basis of such complaint, information, or suspicion that such person has committed the said offence; (ii) the police officer is satisfied that such arrest is necessary— (a) to prevent such person from committing any further offence; or (b) for proper investigation of the offence; or (c) to prevent such person from causing the evidence of the offence to disappear or tampering with such evidence in any manner; or (d) to prevent such person from making any inducement, threat or promise to any person acquainted with the facts of the case so as to dissuade him from disclosing such facts to the Court or to the police officer; or (e) as unless such person is arrested, his presence in the Court whenever required cannot be ensured, and the police officer shall record while making such arrest, his reasons in writing: 2 [Provided that a police officer shall, in all cases where the arrest of a person is not required under the provisions of this sub-section, record the reasons in writing for not making the arrest.] (ba) against whom credible information has been received that he has committed a cognizable offence punishable with imprisonment for a term which may extend to more than seven years whether with or without fine or with death sentence and the police officer has reason to believe on the basis of that information that such person has committed the said offence;] (c) who has been proclaimed as an offender either under this Code or by order of the State Government; or (d) in whose possession anything is found which may reasonably be suspected to be stolen property and who may reasonably be suspected of having committed an offence with reference to such thing; or (e) who obstructs a police officer while in the execution of his duty, or who has escaped, or attempts to escape, from lawful custody; or (f) who is reasonably suspected of being a deserter from any of the Armed Forces of the Union; or (g) who has been concerned in, or against whom a reasonable complaint has been made, or credible information has been received, or a reasonable suspicion exists, of his having been concerned in, any act committed at any place out of India which, if committed in India, would have been punishable as an offence, and for which he is, under any law relating to extradition, or otherwise, liable to be apprehended or detained in custody in India; or (h) who, being a released convict, commits a breach of any rule made under sub-section (5) of section 356; or (i) for whose arrest any requisition, whether written or oral, has been received from another police officer, provided that the requisition specifies the person to be arrested and the offence or other cause for which the arrest is to be made and it appears therefrom that the person might lawfully be arrested without a warrant by the officer who issued the requisition. 1 [(2) Subject to the provisions of section 42, no person concerned in a non-cognizable offence or against whom a complaint has been made or credible information has been received or reasonable suspicion exists of his having so concerned, shall be arrested except under a warrant or order of a Magistrate.]
43. Arrest by private person and procedure on such arrest.—(1) Any private person may arrest or cause to be arrested any person who in his presence commits a non-bailable and cognizable offence, or any proclaimed offender, and, without unnecessary delay, shall make over or cause to be made over any person so arrested to a police officer, or, in the absence of a police officer, take such person or cause him to be taken in custody to the nearest police station. (2) If there is reason to believe that such person comes under the provisions of section 41, a police officer shall re-arrest him. (3) If there is reason to believe that he has committed a non-cognizable offence, and he refuses on the demand of a police officer to give his name and residence, or gives a name or residence which such officer has reason to believe to be false, he shall be dealt with under the provisions of section 42; but if there is no sufficient reason to believe that he has committed any offence, he shall be at once released.
44. Arrest by Magistrate.—(1) When any offence is committed in the presence of a Magistrate, whether Executive or Judicial, within his local jurisdiction, he may himself arrest or order any person to arrest the offender, and may thereupon, subject to the provisions herein contained as to bail, commit the offender to custody. (2) Any Magistrate, whether Executive or Judicial, may at any time arrest or direct the arrest, in his presence, within his local jurisdiction, of any person for whose arrest he is competent at the time and in the circumstances to issue a warrant.