SEATTLE — A legally armed civilian shot and killed a 16-year-old boy Wednesday night after the teen allegedly opened fire on two people in downtown Seattle, according to police. The shooting happened just after 10 p.m. near First Avenue and Union Street. Police said the teen shot two people before he encountered a 57-year-old man licensed to carry a firearm, who then shot the teen. “One individual produced a weapon, fired on the two individuals and then began to flee the scene,” said Seattle Police Chief Shon Barnes. “When he did, he encountered a private citizen that was licensed to...