Syrian helicopters dropped explosives-packed barrels near rebel-held Yabrud on Tuesday, a monitoring group said, nearly three weeks into a major offensive targeting the strategic town near the Lebanese border.

The strikes come a day after at least 15 rebels were killed fighting in the Yabrud area, north of Damascus, said the Syrian Observatory for Human Rights, a Britain-based group relying on contacts inside the war-torn country.

The group supported reports from activists on the ground, who said the village of Sahel is still a contested area, a day after the army claimed it had taken it over completely.