Syrian aerial bombardment on a residential area and a crowded market in a town in northern Aleppo province has reportedly killed dozens of people, including women and children.
Saturday’s attack on al-Bab, which saw helicopters belonging to President Bashar al-Assad's forces drop explosives-filled barrels, killed at least at 28 people, according to Syrian Observatory of Human Rights.
The UK-based group said three children were among the dead.
The Local Coordination Committees activist group, meanwhile, said 29 people were killed. Scores of others were injured.
Al-Bab, 30km northeast of the city of Aleppo, is held by the Islamic State of Iraq and the Levant (ISIL) group and is a frequent target of Syrian military strikes that often kill civilians.
On May 31, regime air strikes that hit a packed market in al-Bab killed at least 55 people, most of them civilians.
A US-led coalition is waging a separate air campaign against ISIL in Syria, but rejects the idea of partnering with Assad, who it sees as an obstacle to peace in Syria.