 In the following two months, Soviet Air Forces conducted several attacks against the King Carol I Bridge, destroying one of its spans and damaging an oil pipeline; see Zveno project.However, after the successful Axis powers' Crimean Campaign and overall deterioration of the Soviet position, Soviet attacks against Romania ceased.The United States Army Air Forces (USAAF) first dropped bombs on Romania on 12 June 1942 during the HALPRO (Halverson project) raid against Ploiești (the first U.S. mission against a European target).