Charges were filed Tuesday in a hit-and-run crash in St. Charles County.
Christopher Wirstrom is accused of hitting 45-year-old Daniel Helfert while he was riding his motorcycle Sunday night. Helftert suffered severe injuries, but survived.
Helfert's son searched the scene and found evidence, which helped lead police to the suspect.
Wirstrom is charged with felony leaving the scene of an accident. His bond was set at $100,000.