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,

The alleged rifleman, Arturo Gamboa, 24, was also shot and was taken into custody on a murder charge, Salt Lake City Police Chief Brian Redd said at a Sunday news conference. The bystander who was killed was identified as Arthur Folasa Ah Loo, 39, a fashion designer from Samoa.

Anti-Trump activists, including civil-rights groups and labor unions, organized the nationwide protest under the banner of “No Kings,” denouncing what they say are Trump’s authoritarian tendencies — and the parade being held on his 79th birthday.