A U.S. drone strike in Syria late Thursday targeted the infamous masked Islamic State executioner named "Jihadi John," the Pentagon said.  But it's unclear if he was killed in the strike. He is known for his brutal beheading of several Western hostages in Syria.

The U.S. military said early Friday it was still working to determine whether the strike killed the militant, a British citizen whose real name is Mohamed Emwazi.  Officially, the Pentagon would only confirm that the strike had Emwazi in its sights. "U.S. forces conducted an airstrike . . . targeting Mohamed Emwazi, also known as "Jihadi John," Pentagon Press Secretary Peter Cook said on Thursday.

Read More:  USA Today