Anti-government rebels in northern Syria have launched a sudden offensive in an effort to capitalize on Israel’s efforts to weaken Iran’s regional proxies.

Rebel forces have launched a major offensive in north-western Syria, capturing territory from President Bashar al-Assad’s forces for the first time in years. The Islamist militant group Hayat Tahrir al-Sham (HTS) and allied factions said they had seized control of a number of towns and villages in Aleppo and Idlib provinces since Wednesday.

The surprise assault occurred around Aleppo, a government-held city and one of the focal points of fighting in Syria’s civil war.