A Vernal man on the sex offender registry who attempted to kidnap and sexually assault a woman last spring has been sentenced to prison. 57-year-old Charles Irwin Alexander was alone with a woman who was planning to smoke heroin with him on May 5th when he held a knife to her throat after she refused to have sex with him and had attempted to leave. The woman fought back and was able to escape. Court documents show that when interviewed, Alexander confirmed the woman’s story. In July, Alexander pleaded guilty to kidnapping, sexual abuse and possession of a dangerous weapon by a restricted person. In 8th District Court this week, Alexander was sentenced to 1 to 15 years in Utah prison for the kidnapping charge and 1 to 15 years for the sexual abuse charge. He was also sentenced zero to 5 years for the weapon charge.