“They bring in the people who they claim left Islam and behead them,” said Mahmoud Sharif, a fighter with Battalion 13, a unit of the Free Syrian Army (FSA) in northern Syria that fights daily against both ISIS and the regime of Syrian President Bashar al-Assad. “Killing is normal for them. They don’t allow anyone to raise their head and speak, but behead them immediately. Any movement, call for change, is not acceptable. They don’t care about humanity; it is their last care.”