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

Syrian government and opposition factions say Syrian armed groups have launched a large-scale attack on areas controlled by government forces, setting off fierce clashes for the second day.

Rebel groups in Syria say they have taken control of villages in the northwest in the first significant fighting with government forces for several years.

Syrian rebel fighters launched their first major offensive in four years against government positions near Aleppo, claiming to have advanced several miles and captured a string of villages.

Russian and Syrian forces have launched airstrikes on northwest Syria to counter a major rebel offensive led by Hayat Tahrir al-Sham near Aleppo

Syrian rebels in the last opposition enclave in northern Syria launched on Wednesday a wide-scale military operation against the Syrian army and seized territory in the first such advance in years, army and rebel sources said.

In a significant escalation, Syrian opposition factions have launched their largest offensive in years against regime and Iranian forces in the Aleppo countryside, reports Rizik Alabi of The Media Line.

Militant rebels in Syria overran an army base and took over at least 13 villages, in one of the biggest flare ups in violence in years in the north-east of the country. The rebels launched a surprise attack on the Syrian army in the northern province of Aleppo,