Oregon Revised Statutes Procedure in Criminal Matters Generally § 133.235

(1) A peace officer may arrest a person for a crime at any hour of any day or night.

(2) A peace officer may arrest a person for a crime, pursuant to ORS 133.310 (1), whether or not such crime was committed within the geographical area of such peace officer's employment, and the peace officer may make such arrest within the state, regardless of the situs of the offense.

(3) The officer shall inform the person to be arrested of the officer's authority and reason for the arrest, and, if the arrest is under a warrant, shall show the warrant, unless the officer encounters physical resistance, flight or other factors rendering this procedure impracticable, in which case the arresting officer shall inform the arrested person and show the warrant, if any, as soon as practicable.

(4) In order to make an arrest, a peace officer may use physical force as justifiable under ORS 161.235, 161.239 and 161.245.

(5) In order to make an arrest, a peace officer may enter premises in which the officer has probable cause to believe the person to be arrested to be present.

(6) If after giving notice of the officer's identity, authority and purpose, the officer is not admitted, the officer may enter the premises, and by a breaking, if necessary.

(7) A person may not be arrested for a violation except to the extent provided by ORS 153.039 and 810.410.