BEIRUT A makeshift bomb dropped from a government helicopter killed at least six people, including two children, in a rebel-held area in northern Syria on Sunday, activists said.
President Bashar Assad's forces have used so-called barrel bombs to devastating effect against opposition areas in Syria. The crude weapons -- barrels packed with explosives and scraps of metal and pushed out of helicopters -- cannot be precisely targeted, and have caused widespread civilian casualties.
Assad's air force tends to use them to push out rebels from contested areas, but to also terrorize civilians and turn them against the fighters in their midst.
Saturday's air raid took place in the town of Sarmeen in the northwestern province of Idlib, activists said.
The Britain-based Syrian Observatory for Human Rights put the death toll at six, but said that number was expected to rise. The Local Coordination Committees activist group and the pro-rebel Shahba Press Agency also reported the airstrike, but provided higher death tolls.
It's common to have conflicting death tolls in the immediate aftermath of bombings.
An amateur video posted online showing the aftermath of the attack, the crushed bodies of men and at least one child were visible amid twisted wreckage, splattered blood, and burning tires.
The video appeared genuine and corresponded with AP reporting of the event.
Activists say the airstrike occurred during clashes in the area between rebels and pro-government forces.
Another airstrike Saturday hit the northern town of Marea, killing a widowed woman and her 7-year-old daughter, said a Marea-based activist who uses the name Abu al-Hassan. The woman's husband was killed in fighting two years ago, Marea said.
The couple's four-year-old son is now an orphan, he added.
Marea and other activists said government forces were stepping up their use of the crude bombs against rebel-held areas in rural parts of northern Syria.
Marea, and another activist who uses the name Abu Raed, said the stepped-up campaign began after rebels from an array of different Islamic groups began attacking government forces several weeks ago at several points around the northern city of Aleppo.
The attack has snubbed an advance by Assad forces toward rebel-held areas of eastern Aleppo.
While pro-Assad forces have been slowly wresting back opposition areas in other parts of Syria, rebels have a strong hold on positions along the northern border with Turkey because it is an easy conduit for fighters and weapons.
Syria's war, now entering its fourth year, has killed over 150,000 people, displaced more than six million and destroyed the country's social fabric and economy.