Thirty civilians have been kidnapped and killed by militants reportedly associated with the Islamic State group in Afghanistan’s Ghor province, Al Jazeera reported on Wednesday. Investigators believe the militants executed the civilians to avenge the death of one of their commanders, who was killed by the police recently. The incident took place in Firoz Koh district on Tuesday.

Abdul Hai Khatibi, a spokesperson for the governor, told the news channel an IS commander was killed on Tuesday and that the abduction and execution of civilians near the provincial capital was done in revenge.

The militants abducted the people, along with two flocks of sheep, from the mountains where they had gone to collect firewood, according to BBC. The militants have been fighting the Taliban for the control over the region. The two militant factions have had several confrontations since January 2015. However, the Taliban claimed on Twitter that they were responsible for the civilian deaths.