US cannot prove Islamic State chief is dead: Mattis

WASHINGTON, Jul 14 : US Defense Secretary Jim Mattis said today that the United States could not prove that Islamic State leader Abu Bakr al-Baghdadi was dead. "If we knew, we would tell you. Right now I can't confirm or deny it," Mattis said. "Our approach is we assume that he's alive until it is proven otherwise, and right now I can't prove it otherwise," Mattis added.