From ND Century Code:
24-03-05. Closing of roads - Penalty for passing over road or removing barricade. Whenever, during the construction work on any state highway or at any other time, it may be necessary to prevent traffic from passing over any portion of such highway, the department may close such portion of the highway to all traffic by causing to be posted in a conspicuous manner, at the ends of the portion of the highway so closed, suitable signs warning the public that such road is closed under authority of law, and by the erection of suitable barricades, fences, or other obstructions. The driver, or owner, or both, of any vehicle, self-propelling or otherwise, passing through, over, or around any such barricade, fence, or other obstruction so placed, or any person opening, removing, or defacing any such barricade, fence, or other obstruction, or any such warning sign, without written permission from the engineer in charge of the work, or in charge of such highway, or any person willfully causing any damage to the work under construction, is guilty of a class A misdemeanor.
Also from the Century Code, the penalty part:
Class A misdemeanor, for which a maximum penalty of imprisonment for three hundred sixty days, a fine of three thousand dollars, or both, may be imposed.