Russia confirmed that a Syrian Mi-25 attack helicopter with two Russian pilots on board was shot down near Palmyra on Jul. 8.
The official reason given was that the pilots, Evgeny Dolgin and Ryafagat Khabibulin, were carrying out a test flight when they were called in by ground commanders to provide air support against ISIS forces.
They had expanded their ammunition and were heading back to base when their helicopter was attacked. Both of them did not survive the crash.