U.S.-led coalition targeting a village in northern Syria held by the Islamic State group killed 28 civilians, including seven children, Syrian activists said Friday.

The Britain-based Syrian Observatory for Human Rights said aircraft belonging to the coalition struck the village of al-Ghandour late on Thursday previous night.

Observatory's chief Rami Adurrahman said another 13 people were killed in the strikes but that he could not say if they were ISIS fighters or civilians. Al-Ghandour is 15 miles northwest of the town of Manbij, a key hub in the extremist group's Syria network and a supply route to ISIS' de facto capital of Raqqa.

The international coalition had no immediate comment on the casualty figures reported by the Observatory. The bombings came a week after airstrikes, also blamed by Syrian activists on U.S. aircraft, killed at least 56 civilians in Islamic State-held territory in northern Syria.

The Manbij area has seen extensive battles between ISIS extremists and U.S.-backed Kurdish-led fighters, who have been advancing under the cover of airstrikes by the U.S.-led coalition. The town is encircled by the Kurdish-led forces.

The Kurdish-led forces were able to evacuate another 1,000 civilians from Manbij Thursday, according to Mustafa Bali, a local media activist living in the town of Kobani.

"There has been a lot of pressure on the militants in Manbij," said Bali.

Late Thursday, the U.S. Central Command, which is responsible for U.S. forces in the Middle East, said in a statement that the American-backed coalition had conducted airstrikes in the area of Manbij during the past 24 hours and that it was looking into whether an airstrike had resulted in civilian casualties.

It was not clear if the Manbij-area strikes that CENTCOM cited involved strikes on al-Ghandour.