Okla. Stat. tit. 69 § 1209
The Commission, its officers, agents, servants and employees shall have authority to physically remove any such sign, post, thing or structure, gasoline pump, driveway canopy, fence, signpost and building; and if the owner of any such driveway canopy, gasoline pump, or building, thing or structure fails to remove the same within a reasonable time after written demand for the removal thereof has been made upon him by registered mail or personal service, the Commission, its officers, agents, servants and employees may physically tear down and remove such building, canopy, or pump, and for such purpose may enter upon private property to the extent necessary to accomplish the removal. Neither the state nor the Commission or its agents, servants, officers and employees shall be liable for any damage caused or sustained by reason of the abatement and removal of any such nuisance.
Okla. Stat. tit. 69, § 1209