Fierce battles erupted Tuesday in the city of Aleppo, a northern Syria battleground for the past six months, as rebels fought troops near an army barracks and tanks shelled the area, a watchdog said.
In the countryside surrounding Aleppo, once Syria's thriving commercial capital but now ravaged by war, troops also shelled the rebel-held towns of Al-Bab and Sfeira, the Syrian Observatory for Human Rights said.
"Battles pitting rebels against troops broke out at dawn Tuesday ... near the Mahlab army barracks (in Aleppo) ... while army tanks shelled the area. Both sides have sustained casualties," said the Observatory, which relies on a broad network of activists, doctors and lawyers for its information.
It gave no further details of the casualties.
Tuesday's violence comes a day after the army seized from rebels the town of Khanasser in eastern Aleppo province, according to residents.
"The army retook Khanasser after it used warplanes and tanks to bombard it," one resident said, speaking to AFP on condition of anonymity.
The resident added that the town's rebels were loyal to the jihadist Al-Nusra Front -- a group listed as a "terrorist" network by Washington.
Elsewhere in the strife-torn country, tanks renewed shelling of the rebel-held towns of Talbisseh and Ghanto in the central province of Homs, said the Britain-based Observatory.
The army, meanwhile, sent reinforcements to rebel town Daraya, southwest of Damascus, activists said, pressing an offensive to reclaim the area considered strategic because of its proximity to the capital and to the Mazzeh military airport.
The United Nations says more than 60,000 people have been killed in violence across Syria since the outbreak of a revolt in March 2011 that morphed into an insurgency after the army launched a brutal crackdown on dissent.