"In this March 21, 2017 photograph, Mohammmed, last name not given, shows a tattoo on his forearm that reads in Arabic: ""All for you, mother"", during an interview with The Associated Press, in Gaziantep, southeastern Turkey. He was barely 20 when Islamic State group militants stormed his home city of Deir el-Zour in the oil-rich east of Syria. Mohammed had already been fighting government forces the past two years, so it was an easy decision for him: Join the militants to keep up the battle against President Bashar Assad's rule. (AP Photo/Lefteris Pitarakis)"