-504§ 3733. Peace officers defined The following are peace officers: (1) the marshal and deputy marshals; (2) constables of the magistrates' courts; and (3) all officers and memfers of the police force. § 3734. Arrests by peace officers with or without warrant A peace officer may make an arrest in obedience to a warrant. He may arrest a person without a warrant when: (1) he has reasonable cause to believe that the person to be arrested has committed a public offense in his presence; (2) the person to be arrested has committed a felony, although not in his presence; or (3) he has reasonable cause to believe that the person to be arrested has committed a felony, whether or not a felony has in fact been committed. § 3735. Arrests by private persons A private person may arrest another: (1) for a public offense committed or attempted in his presence; (2) when the person arrested has committed a felony although not in his presence; or (3) when a felony has been in fact committed and he has reasonable cause for believing the person arrested to have committed it. § 3736. Oral order for arrest The district judge. United States attorney, or a magistrate may orally order a peace officer or private person to arrest anyone committing or attempting to commit a public offense in the presence of the judge, United States attorney or magistrate. § 3737. Authority to summon assistance (a) A peace officer attempting to serve a criminal process issued by a court or other authority, may summon a sufficient number of men to assist in the arresting or safekeeping of a person who refuses to be taken or who is likely to make his escape. (b) A person making an arrest may orally summon as many persons as he deems necessary to aid him therein. § 3738. Time of arrest If the offense charged is a felony, an arrest may be made on any day and at any time of day or night. If it is a misdemeanor, an arrest may not oe made at night, except upon direction of a magistrate by indorsement on the warrant or except when the offense is committed in the presence of the arresting officer. § 3739. Manner of making arrest A person making an arrest shall inform the person to be arrested of the intention to arrest him, of the cause of the arrest, and the authority to make it, except when the person making the arrest has reasonable cause to believe that the person to be arrested is actually engaged in the commission of or an attempt to commit an offense, or the person to be arrested is pursued immediately after its commission, or after an escape. § 3740. Use of all reasonable means If a person about to be arrested either flees or forcibly resists, after he has oeen informed of the intention of the arresting officer to place him under arrest, the officer may use all reasonable means to effect the arrest.