Three people were killed and several injured Sunday when a casino bus carrying a group of tourists in northwestern Mississippi overturned on its way to the airport, officials said. The bus belonged to Harrah's Tunica and was carrying 43 people when it flipped over in a median at an intersection in Tunica, Tunica County spokesman Larry Liddell said. Tourists on the bus were traveling to the airport for a flight to South Carolina, where many were from, officials said. The bus was the only vehicle involved in the accident, which was still under investigation, Mississippi Highway Patrol Sgt. Leslie White said. The injured passengers were taken to hospitals in Memphis, Tennessee, about 56 kilometers to the north.