Topeka, Kansas (AP) - The same week Harrah's Entertainment Inc. is being considered for a contract to manage a Kansas-owned casino in Sumner County, it has been sued by an Indian tribe whose casino it managed for a decade. The Prairie Band Potawatomi Nation filed the lawsuit against Harrah's, alleging the company violated a noncompete agreement with the tribe by seeking the contract for a proposed facility near Mulvane.