Relentless air strikes against the rebel-held section of the divided Syrian city of Aleppo continued Saturday, with many buildings destroyed down to the basements.
The Britain-based Syrian Observatory for Human Rights says at least 25 people have been killed Saturday. The previous day, at least 30 people, including several children were reported to have been killed by Russian and Syrian airstrikes.
Witnesses say the surge in airstrikes began late Wednesday after the Syrian government announced a renewed offensive to recapture the entire city. That follows the failure by the U.S. and Russia to salvage a cease-fire that had defused hostilities for nearly a week.
The intense air strikes are targeting residential areas and buildings used by the volunteer group known as the "White Helmets."
Aleppo, the country's second biggest city, has been divided among government troops, rebel militias, Islamic extremists and Kurdish fighters since 2012.
One member of the Syria Civil Defense group told the Associated Press that the renewed bombardment is the most intense of the war.
He claimed the attacks were in retaliation for the group, also known as the White Helmets, winning the international "Right Livelihood Award" Thursday in recognition of their efforts to rescue and provide medical care for those wounded in the strikes.
The group says the full extent of the casualties remains unclear because the intensity of the bombing has prevented workers from reaching victims of the latest strikes.