VIDEO: The Madison County Sheriff’s Department say social media and security cameras helped lead them to two teenager arson suspects. On Saturday morning the historic Cedar Bridge near Winterset was intentionally set on fire. On Tuesday authorities arrested 17-year-old Alex Hoff of West Des Moines and charged him with 1st Degree Arson. On Wednesday 18-year-old Joel Davis of Norwalk was arrested as well. According to court documents, authorities say they learned early in their investigation that Hoff had a “personal connection” to the bridge and had talked about burning it down. They also discovered an Instagram post of him standing inside another covered bridge with the message “The hardest part of life is knowing which bridges to burn, and which to cross”.