US Coalition Airstrikes Kill 56 Civilians in Syria: Report

Among the casualties were 11 children, according to the report.

— -- Airstrikes in northern Syria allegedly led by a U.S.-backed coalition killed at least 56 civilians and injured dozens of others, according to the Britain-based Syrian Observatory for Human Rights.

Among the casualties were 11 children, according to the human rights group.

U.S. coalition airstrikes have been supporting the Syria Democratic Forces, which weeks ago began an offensive to take over the Manbij territory on Syria's border with Turkey. The territory is currently a stronghold of Islamic State insurgents.

"We are aware of reports alleging civilian casualties near Manbij, Syria, recently. As with any allegation we receive, we will review any information we have about the incident," said Defense Department spokesman Matthew Allen said in a statement.

Brett McGurk, the special presidential envoy for the Global Coalition to Counter ISIL, told reporters that he was unable to confirm reports and cautioned that the "initial allegations arose from ISIL’s official news channel."

He said the military takes extra measures to "make sure that every airstrike is really carefully vetted."

ABC News was unable to independently verify the figure.

"We take all measures during the targeting process to avoid or minimize civilian casualties or collateral damage and to comply with the principles of the Law of Armed Conflict," said Allen.

As of late May, the Observatory reports, at least 100 civilians have died from U.S.-led airstrikes targeting Manbij.

Amnesty International said in a statement today that since June, more than 100 civilians have been reportedly killed in suspected attacks by the U.S.-led coalition in the Manbij area.

As of April 25, coalition airstrikes have killed 41 civilians and injured 28 others in Iraq and Syria, according to U.S. Central Command.