Syrian rebels launched a series of attacks on army positions on Sunday as regime air strikes hit opposition-held towns near Damascus after the failure of a Muslim holiday ceasefire effort, a watchdog said.
Rebels took control of three military posts in the outer Damascus suburb of Douma and killed four soldiers at another checkpoint in the region, the Syrian Observatory for Human Rights said.
Regime warplanes hit targets in the towns of Irbin, Zamalka and Harasta, where the military has been trying for weeks to dislodge rebel forces, the group said.
The fighting came after the failure of efforts to impose a four-day ceasefire in the battle-scarred country for Eid al-Adha, which started on Friday.
The truce collapsed only hours after it began amid clashes, shelling and car bomb attacks, with 23 killed on Sunday, according to a preliminary count compiled by the Observatory.
Among them were nine civilians, seven rebels and seven regular troops, it said.
In Aleppo, fierce fighting broke out in several districts of the embattled city, as the army shelled two neighborhoods including the ancient souks in the heart of Syria's second city, it said.
The souks are part of Aleppo's UNESCO-listed Old City district. They were hit by a fire caused by the fighting in late September.
In the province of Aleppo, rebels set free some 120 Kurds taken hostage after clashes between Kurdish militia and anti-regime fighters, said the Observatory.
Observatory director Rami Abdel Rahman warned that scores of Kurds remain captured. "Half of those taken hostage on Friday have been released," he said.
Meanwhile, protests against the presence of armed groups broke out on Sunday in the rebel-held town of Aazaz, near the Turkish border, the Observatory and activists said.
Armed groups who fight independently from the main rebel Free Syrian Army are believed to be holding scores of people captive in Aazaz, including a Lebanese journalist, Fida Itani, whose capture was reported on Saturday.
"People took to the streets in Aazaz to protest against armed groups inside the town and to denounce their intervention in civilian affairs," said Aazaz-based anti-regime activist Abu Mohammed.
"They also called for those being held captive without charge to be released."
In the neighboring province of Idlib, the army tried to retake the town of Maaret al-Numan, which rebels seized on 9 September, said the Observatory.
Rebels destroyed an army tank and killed three soldiers in the fighting, it said.
According to the Observatory, more than 35,000 people have been killed in the conflict, which began as an anti-regime uprising but is now a civil war pitting mainly Sunni rebels against a regime dominated by Assad's minority Alawi sect, an offshoot of Shia Islam.
The Britain-based Observatory relies on a countrywide network of activists, lawyers and medics in civilian and military hospitals.
