A 16-year-old boy shot five people in a confrontation between two groups at a carnival in a Salt Lake City suburb, killing three of them including an 8-month-old boy.

Utah officials are investigating the role that so-called peacekeepers played in the killing of celebrated fashion designer Arthur Folasa Ah Loo on Saturday at the “No Kings” demonstration in Salt Lake City,

A bystander was fatally shot after security members at the demonstration confronted a man who was running toward the crowd with an AR-15-style rifle, the police said.