A Bellevue gun collector was arrested and held for 23 days as a material witness in the slaying of federal prosecutor Thomas Wales, according to court records, jail logs and people familiar with the investigation. The man is not considered a suspect in Wales' killing, but he was jailed in January as part of the FBI's nationwide search for a unique gun barrel used in the crime. Wales was shot to death while sitting at a computer in the basement of his Queen Anne home on Oct. 11, 2001. Shell casings and slugs found at the scene and recovered from...