Over 40 U.S.-backed fighters were killed fighting the Islamic State group in eastern Syria this weekend, the Syrian Observatory for Human Rights reported on Saturday, October 27, Al-Masdar News reports.

According to the SOHR report, the Islamic State killed at least 41 members of the U.S.-backed Syrian Democratic Forces near the strategic town of Hajin in the southeastern countryside of the Deir Ezzor Governorate.

The Islamic State’s official media wing, Al-‘Amaq, would later corroborate the report, while also posting a video of their militants capturing six members of the Syrian Democratic Forces alive.

The militant group was able to repel another big attack by the Syrian Democratic Forces forces near the IS stronghold of Hajin this weekend after an intense battle that lasted for several hours on Thursday and Friday.

The Syrian Democratic Forces have repeatedly attempted to crack the Islamic State’s lines near Hajin; however, their attacks have been repeatedly repelled by the militant group.