The Kurdish SDF said the two Americans captured on Monday were hiding out in the Islamic State’s last stronghold in E. Syria and identified them as Warren Christopher Clark, 34, and Zaid Abed al-Hamid, 35. Three other suspected foreign Islamists were also detained. George Washington University’s Program on Extremism said that Clark, a Texan, had converted to Islam and applied for an English-teaching job at the University of Mosul in Iraq when it was under ISIS occupation. He called himself Abu Muhammad al-Ameriki. Little is known about Hamid.