Miami\'s mayor asked the Justice Department to probe the city\'s Police Department after seven deadly police shootings of black men rocked Miami\'s inner city. \"In light of the growing concern in the community regarding police practices and police accountability, I have concluded that an external investigation by [the Justice Department] would provide the resources, expertise and independence to begin to transform the department and assuage police-community tensions,\" Mayor Tomas Regalado wrote to U.S. Attorney General Eric Holder Wednesday. Regalado -- who has engaged in a public battle with Miami Police Chief Miguel Exposito for more than a year -- wrote he was concerned not only about the \"pattern\" of shootings but also about the \"apparent lack of response\" to questions from relatives and the community, The Miami Herald reported. All but one of the shooting deaths remain under investigation by the state attorney\'s office and police. Both agencies refuse to discuss open investigations. Exposito told the Herald he \"welcomed any federal probe into our police department.\" He said the same thing in February in a letter to the Herald after the last of the shootings after earlier demands for a Justice Department review.