At least four people were killed and 40 injured when a stage structure collapsed at the Indiana State Fairgrounds. The incident occurred late on Saturday night when a wind gust brought down the stage rigging prepared for a country music concert shortly before 9:00 pm (0100 GMT Sunday), police said. Nobody was performing at the stage when the tragedy occurred. Witnesses said the opening act had finished, and the crowd was waiting for the country music band Sugarland to begin its concert.