BEIRUT (AP) — Syrian government warplanes pounded an Islamic State group stronghold as well as other towns controlled by the extremists, conducting a wave of airstrikes Sunday that killed at least 11 people, activists said.

For more than a year, President Bashar Assad’s air force rarely targeted territory controlled by the Islamic State group in northern Syria, instead focusing on mainstream rebel groups. But government jets have begun hitting the extremists more regularly since the jihadis overran much of neighboring northern and western Iraq in June.