HARRISBURG, Pa. (AP) — A member of the U.S. Marshals Service was shot and killed early Thursday while serving a warrant, the mayor of Harrisburg said. Two other officers were also shot, including a Harrisburg police officer who "bravely returned fire and critically injured the gunman," Mayor Eric Papenfuse said. York City Police said one of its officers was shot and was taken to a hospital for treatment of non-life-threatening injuries.