PORTLAND, Ore. (AP) — Several people were arrested after a demonstration turned violent in downtown Portland, Oregon, and resulted in damage to two government buildings. Police said in a statement that protesters broke into the Justice Center late Thursday and broke glass doors to the federal courthouse nearby. They threw cans of food, large rocks and commercial-grade fireworks at federal officers who responded to the scene. The statement released Friday said protesters also set a fire on the street. Protesters were warned twice that a riot would be declared, a sign that harsher tactics would be employed, if they did not leave the area.