The 12-story hotel has 325 rooms with a spa, fitness center and pool. The casino property boasts more than 1,300 slot machines and more than 50 table games. The Mississippi casino is currently owned by Premier Entertainment Biloxi LLC, a subsidiary of Leucadia National Corp. The sale is expected to be complete in June. Twin River Worldwide Holdings made the announcement Sunday. The company that owns Twin River Casino in Lincoln is buying the Hard Rock Hotel & Casino Biloxi in Mississippi for about $250 million.