The Britain-based Syrian Observatory says coalition aircraft struck Northern Syria on Thursday night.
Syrian activists say US-led coalition airstrikes targeting a village in northern Syria held by the ISIS group killed 28 civilians, including seven children.
The Britain-based Syrian Observatory for Human Rights says coalition aircraft struck the village of Al-Ghandour on Thursday night.
Observatory's chief Rami Adurrahman says another 13 people were killed in the strikes but that he couldn't say if they were ISIS fighters or civilians.
It was also unclear if the Al-Ghandour strikes involved an airstrike reported on Thursday by the US Central Command, which is responsible for US forces in the Middle East.
CENTCOM said the coalition had conducted airstrikes in the area of the town of Manbij in the past 24 hours and was looking into reports that there were civilian casualties.
Al-Ghandour is near Manbij.