The Syrian Network for Human Rights has issued a new report, in which they determined US warplanes have killed over 100 civilians in airstrikes in Syria since September

Nearly half of the 103 deaths were the result of a single strike, on December 28, when US planes attacked a makeshift ISIS prison in al-Bab, killing 51 civilians held therein.

The al-Bab incident was initially denied by the Pentagon, and only confirmed two weeks later after an investigation by McClatchy. The Pentagon then conceding leveling the building, but said they didn’t consider the death toll credible.

Many of the civilian deaths in the Syria attacks have been the result of the US targeting refineries in ISIS territory, which are being run by civilians. The strikes are meant to be hurting ISIS’ revenue streams, but are killing civilians and crippling the civilian infrastructure of the region.