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.

Arthur Folasa Ah Loo, 39, a Samoan-born fashion designer, was participating in an anti-Trump protest in Salt Lake City on Saturday when he was shot by a man working security, the police said.