Salt Lake City police are investigating the roles of two self-described "peacekeepers" following a fatal shooting at Saturday's protest that left one person dead and another injured, raising questions about unauthorized security at public demonstrations.

An "innocent bystander" at the "No Kings" demonstration in downtown Salt Lake City was shot and killed Saturday, police said

Arthur Folasa Ah Loo, 39, has died as the result of a gunshot wound he sustained Saturday in a shooting during a protest against President Donald Trump in Salt Lake City.

Donations have flooded in for the widow and children of an innocent bystander killed by a stray bullet during an anti-Trump demonstration in Utah.

A man who was believed to be part of a peacekeeping team for the “No Kings” protest in Salt Lake City shot at a person who was brandishing a rifle at demonstrators, striking both the rifleman and a bystander who later died at the hospital, authorities said Sunday.