At approximately 4:00 pm, protester activity began. Initially, limited numbers of protesters were in the area directly east of the HDD site as well as at Turtle Hill. At approximately 5:00 pm, there were approximately 200 protesters in the general areas of the HDD site and Turtle Hill. Approximately 75 were by the HDD site, 40 by Turtle Hill, and the remainder were scattered in the general area. Protesters cut and removed the security wire in the area east of the HDD site. Law enforcement arrested 3 protesters in the area east of the HDD site during this activity. At approximately 6:00 pm, the protesters began gathering on the Backwater Bridge and were relocating from the other protest areas to the bridge. The number of protesters at the bridge continued to grow. At approximately 7:50 pm, protesters began removing the security wire and other barricade materials at the north end of the bridge. A protester also crossed over the barricade and disabled the security lights at the bridge.Some protesters were equipped with shields and gas masks. At approximately 9:55 pm, law enforcement officers crossed the barricade and pushed the protesters back to the south end of the bridge. As law enforcement returned back to the north side of the barricade, the protesters again advanced back to the barricade on the north end of the bridge and continued to remove the security measures at the barricade. A standoff continued at the barricade between law enforcement and the protesters with occasional protesters arrested by law enforcement as the protesters either crossed the barricade or law enforcement crossed over to the south side of the barricade and made arrests. A total of 11 protesters were arrested during the protest activity at the bridge. By approximately 1:00 am, the protesters had mainly dispersed from the bridge with only a few remaining at the bridge at that time. No further significant protest activity was occurring at that time. Law enforcement did utilize chemical agents and less lethal munitions at times during the protest activity. Protesters were reported as throwing items at law enforcement on occasion and also targeted the NDHP airplane with spotlights and lasers.