The Observatory, which monitors the conflict through a network of activists on the ground, also reported air raids Monday on Aleppo, a day after government helicopters dropped barrels packed with explosives on opposition neighborhoods in the city.
The government frequently uses barrel bombs, which contain hundreds of kilograms (pounds) of explosives and cause massive damage on impact.
The Observatory raised its death toll from Sunday's carnage, saying at least 76 people were killed, including 28 children.
Another activist group, the Local Coordination Committees, put the death toll at 83.
It said that number is likely to rise because of the large number of wounded and the lack of sufficient medical supplies.
