An air strike on a market on Thursday killed at least 27 people, including three children, in a village of the north Syrian province of Aleppo, a monitoring group said.
The deadly raid comes amid a massive aerial offensive targeting opposition-held areas across Aleppo city and province that began in mid-December.
The Syrian Observatory for Human Rights said the bombing campaign has killed hundreds, mostly civilians, and forced thousands of families to flee their homes.
"The number of people killed in an air strike this morning on the market area of Atareb village has risen to 25, including two women and three children," said the Observatory, updating its toll from 21 dead.
Activists distributed video showing scenes of chaos, with bodies lying amid mounds of grey rubble in what was clearly a market.
The amateur footage shows a woman in a white headscarf screaming as she leaned over the body of a loved one.
Another image showed a man attending to a boy whose leg had been ripped off. It was unclear whether the child was alive or dead.
"The area that was struck today is a market area, that`s why there were so many civilians killed," said Aleppo-based activist Abu Omar.
"The regime is hitting back against the civilians who support the revolt" against President Bashar al-Assad, he added.
Swathes of Aleppo city and province have been out of army control since 2012.
Human Rights Watch has accused Syria`s regime of "wreaking disaster" with its air strikes on the area.
Elsewhere, the army pounded Mleiha east of Damascus amid fierce clashes pitting rebels and their jihadist Al-Nusra Front allies against troops backed by Lebanon`s Shiite Hezbollah and other paramilitary groups, said the Observatory.
Mleiha has been under sustained bombardment since April 3. It is located in the strategic Eastern Ghouta area east of Damascus, swathes of which are besieged by the army and under opposition control.
In southern Damascus, the UN was allowed to distribute 300 parcels of food aid in besieged Yarmuk, after a 15-day lull, said UN Relief and Works Agency spokesman Chris Gunness.
More than 100 people have died in the past year from food and medical shortages in Yarmuk, a Palestinian neighbourhood now home to some 18,000 people.
The Syrian conflict, which broke out in March 2011 after the regime unleashed a massive crackdown against a protest movement demanding political change, is estimated to have killed 150,000 people.
The violence has forced nearly half of Syria`s population to flee their homes.