On Thursday, a U.S. drone strike was launched targeting "Jihadi John," the Islamic State militant linked to the beheadings of several Western hostages, U.S. officials said. Pentagon press secretary Peter Cook said a strike took place near Raqqa, the Syrian city that has become the de facto capital of the Islamic State, and officials are still trying to determine if Jihadi John, a Briton whose real name is Mohammed Emwazi, was killed.