Update Nov. 25 at 11:15 p.m.Kobman has been safely located in Florence, and the Golden Alert has been canceled, according to the sheriff's department. Original: The Boone County Sheriff's Office has issued a Golden Alert D for a missing 17-year-old boy with autism named Caden Kobman.Kobman is a white male around five feet nine inches tall, weighing around 150 pounds, who wears glasses. According to a release from the sheriff's office, Kobman was last seen wearing a white, long-sleeved New York Yankees shirt with green Christmas pajamas and hiking boots. The sheriff's office says that he left his home on Irish Way at around 5 p.m. on Monday on Trek Mountain Bike. His family says that he was riding to Hempsteade Park off Hempsteade Drive in Union, but never returned home.Anyone with information on his whereabouts should call 911 immediately. A search for Kobman is ongoing.