The Dodge County Sheriff's Department is asking for the public's help after a car struck and critically injured a pedestrian and then fled the scene at around 2:30 Sunday morning on Madison Street just south of the Beaver Dam city limits. Sheriff Pat Ninmann says a witness indicated that he and the victim were walking southbound on Madison Street from Lake Crest Drive, when a dark colored sedan came up behind them at an estimated 40 to 45 mph and struck the victim. The vehicle did not stop and left the scene traveling southbound. A witness indicated that there should be significant damage to the right front corner of the vehicle and possibly the windshield. The 33 year old male victim of Beaver Dam was taken to Beaver Dam Community Hospital and then transported to UW Hospital in Madison for life threatening injuries. Anyone with information is asked to contact the Sheriff's Department at 920-386-3726. Callers may remain anonymous.