The Syrian government has evacuated about 5,000 people from an embattled industrial town near the capital Damascus, where rebels linked to al-Qaeda have been battling government troops for more than two weeks.
The evacuation on Sunday comes as the Syrian Observatory for Human Rights (SOHR) said that more than 500 people, including 151 children, have been killed during weeks of government air strikes on opposition-held areas of the northern city of Aleppo and its suburbs.
The majority of the dead were civilians, said the human-rights watchdog, which relies on a network of activists, doctors and lawyers on the ground.
"The Observatory considers all those who remain silent in the international community as complicit in the massacres that have been committed and continue to be committed by the Syrian regime," the group said in a statement.
On Saturday, helicopters dropped TNT-packed barrels on a vegetable market and next to a hospital in Aleppo city, killing at least 25 civilians. The Syrian government has not commented on the aerial campaign.
Opposition fighters from Jabhat al-Nusra swept into Adra, northeast of Damascus, in mid-December, reportedly killing civilian members of the Alawite and Druse sects, minority communities that support President Bashar al-Assad.
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Shortly afterwards, Syrian soldiers surrounded the area, and there has been heavy fighting there since.
On Sunday, Social Affairs Minister Kinda al-Shammat said more than 5,000 people were evacuated from the town.
In a statement carried by the SANA state news agency, Shammat said the people were moved to a safe place, and the ministry was offering aid and support.
Meanwhile, at least 19 rebels were killed in eastern Syria on Sunday in days of fierce fighting between rebels and government troops for control of the Deir Ezzor military airbase, the human-rights watchdog said.
Rami Abdel Rahman, SOHR's chief, said the rebels succeeded in taking control of part of al-Jafra village, a few hundred metres from the airport. Residents of the village support Assad, he said.