A police officer shot and killed a man who had injured him with a knife while resisting arrest in Madison, Wisconsin, the city's police chief said. Video of the shooting shows a struggle between the man and four officers before three gunshots are heard. The man who was shot later died at the hospital, authorities said. The man's name has not yet been released. All four officers will be placed on administrative leave, as is standard protocol for the Madison Police Department, during the investigation. #madison #wisconsin