Wisconsin Gov. Scott Walker activated his state’s National Guard on Sunday to help police in Milwaukee if violent protests persist following the fatal shooting of a man by officers who said he was fleeing a traffic stop. At least four businesses were burned and police officers hurt in violence that broke out Saturday night a few hours after the officer-involved shooting. Police said the man had a handgun. Milwaukee police say both the man whose fatal shooting sparked violent protests in the city and the police officer who shot him are black. Chief Edward Flynn made the disclosure at a news conference Sunday.