Syrian rebels have launched a large-scale attack on regime forces in western Aleppo, according to a Free Syrian Army source and local residents, marking the first major flare-up in years between both sides.

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.

Scores of people were killed after forces opposed to the government of President Bashar al-Assad overtook a Syrian military base, a monitoring group reported.

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Syrian rebel group Hayat Tahrir al-Sham and its allied factions launched a surprise attack on the Syrian army in the northern province of Aleppo. Violent clashes that followed have killed nearly 60 combatants so far.

The death toll from clashes between militants and Syrian government forces in north-western Syria has risen to 57, a monitor group said Wednesday. The Syrian Observatory for Human Rights reported that 31 Syrian soldiers were killed in the fighting that broke out in the north-west of the country in Aleppo governorate.

Syrian rebels have launched a new offensive in the northwest, reportedly capturing several villages, as regime forces launched airstrikes on opposition towns

Syrian rebels launched a surprise attack on the Syrian army in the northern province of Aleppo on Wednesday, sparking clashes in which 57 combatants