Beirut: At least 18 civilians were killed in a single regime barrel bomb attack in Syria`s northern city of Aleppo on Thursday, a monitoring group said.
The Syrian Observatory for Human Rights said the bomb, dropped from a helicopter, struck an eastern sector of the divided city where people were gathering to buy and sell fuel.
In the northern province of Idlib, seven civilians were killed in a regime air strike near a school, Rami Abdel Rahman, the head of the Britain-based Observatory, told a news agency.
The deaths came after UN envoy Staffan de Mistura dispatched a delegation to Aleppo in efforts to freeze fighting there.
On Sunday, a rebel coalition rejected his plan, saying that, among other problems, it did not address the "regime`s use of... barrel bombs prohibited by the international community".
The government has regularly dropped barrel bombs on opposition areas across the country, particularly rebel-held parts of Aleppo province.
Rights groups have criticised the bombs -- crudely constructed from barrels packed with explosives -- as indiscriminate, citing the large number of civilians they kill.
Assad has denied the Army uses them.