Following the Six-Day War, from 1967 to 1970, there were small scale incursions into the Israeli-held Sinai desert as Egypt rearmed. This evolved into large-scale artillery and air incursions in 1969, with Soviet pilots and SAM crews arriving to assist in January 1970. The strategy was to engage Israeli aircraft in surprise fighter encounters near the Suez Canal where Egyptian SAMs could be used to assist fighters.