A federal judge in South Dakota has sentenced an Old West re-enactor to 7 1/2 years in prison for firing into a crowd of tourists and injuring three people. Paul F. Doering, 49, signed a plea agreement in which he admitted concealing evidence involving the re-enactment of a gunfight in June 2011, the Rapid City (S.D.) Journal reported. Doering fled the scene immediately after the performance, police said. He threw away four spent cartridges and buried the remaining live rounds. Police said Doering initially told them he didn\'t know one of the guns had live ammunition but later admitted it did. \"It\'s an absolute miracle that someone wasn\'t killed,\" said U.S. District Judge Jeffrey Viken before sentencing Doering. Because of previous felony convictions, Doering was not supposed to own or possess a firearm or ammunition. He was charged with a violation of federal law but was allowed to plead guilty to a lesser charge of tampering with evidence, prosecutors said.