The U.S. says airstrikes on Syria will continue, despite reports of dozens of civilian deaths and the pleas of opposition activists and human rights groups.

The Guardian reports:

Anas Alabdah, president of the Syrian National Coalition, has called on the U.S. to suspend its airstrikes until it performs a thorough investigation into the attack near the contested northern city of Manbij on Tuesday that Syrian activists say killed at least 73 civilians—and possibly more than 125. [....] The U.S. has launched at least 12 airstrikes since the destruction in the village of Tokkhar, according to a daily tally released by the military. Asked by the Guardian if the military will pause airstrikes, Army Colonel Christopher Garver, chief spokesman for the U.S. military command in Iraq and Syria, replied: "No. Operations continue against Daesh," another name for ISIS.

The escalation in violence follows U.S.-backed Syrian fighters giving ISIS militants 48 hours to leave Manbij as part of a "last-ditch effort to protect civilian lives," the Associated Press reports.

UNICEF estimated this week that "35,000 children are trapped in and around Manbij with nowhere safe to go. In the past six weeks, and as violence has intensified, over 2,300 people were reportedly killed in the area, among them dozens of children."

“We deplore all forms of violence and urge all parties to the conflict in Syria to make every effort to avoid the loss of civilian lives," the group said.

The AP continues:

The fighting around Manbij coincides with an uptick in fighting in the contested city of Aleppo where government forces have completely encircled the eastern, rebel-held parts of the city, trapping hundreds of thousands of people inside. Stephen O'Brien, the U.N.'s emergency relief coordinator, said he is "gravely alarmed" by developments in eastern Aleppo. "Food in east Aleppo is expected to run out by the middle of next month," he warned.

The news also comes as the International Committee for the Red Cross (ICRC) warns that the situation in Aleppo, Syria's largest city, is "devastating and overwhelming," with every neighborhood coming under heavy fire in recent days.

"We hear that dozens of civilians are being killed every day and scores more injured from shells, mortars and rockets. The bombing is constant. The violence is threatening hundreds of thousands of people's lives, homes and livelihoods," said Marianne Gasser, head of the ICRC's Syria delegation, in a statement on Thursday.