A leaked audio recording between an air traffic controller and an Iranian pilot appears to show aviation authorities were aware that a Ukrainian passenger jet had been shot down last month, killing all 176 people on board. The Iranian government denied it was involved in the plane’s downing for three days following the crash, before conceding the Iranian Revolutionary Guards accidentally launched a missile at the Boeing 737 jet. Tehran has said it is halting cooperation with Kiev following the release of the leaked exchange by Ukrainian media Sunday.