A peacekeeper at a “No Kings” protest in Salt Lake City opened fire on a man who raised a rifle at the crowd, but accidentally shot and killed a bystander, police said on Sunday.The incident happened on Saturday evening during nationwide “No Kings” protests, where demonstrators rallied against what they called president Donald Trump’s authoritarian actions. While most protests remained peaceful, violence broke out in Salt Lake City when a man, identified as Arturo Gamboa, 24, pulled out a rifle near the protestors.According to Salt Lake City police chief Brian Redd, two men wearing neon green vests, believed to be part of the peacekeeping team, approached Gamboa with their handguns drawn. Witnesses said Gamboa raised his rifle and moved towards the crowd. One of the peacekeepers then fired three shots, hitting Gamboa and a bystander, Arthur Folasa Ah Loo, 39.Ah Loo was taken to hospital but later died from his injuries. Gamboa, who was treated for minor injuries, was arrested and charged with murder. Police accused him of creating the dangerous situation that led to Ah Loo’s death.The gunfire caused panic, forcing hundreds of protestors to flee, hide behind barriers and seek shelter in nearby buildings. Police recovered an AR-15 style rifle, a gas mask, and a backpack at the scene. Authorities are still investigating why Gamboa brought the rifle to the protest and how the peacekeepers were organised or trained for the event.In another incident in Riverside, California, a driver struck a woman participating in a separate “No Kings” demonstration and fled. The woman was hospitalised with serious injuries but is stable. Police are still searching for the driver.The Utah chapter of the 50501 Movement, one of the groups behind the protests, condemned Gamboa’s actions and thanked first responders and their safety team for acting quickly. They did not respond to questions about the peacekeeping team’s organisation or training.