Russia's claim it killed Islamic State's Adnani 'a joke': U.S. officials

WASHINGTON (Reuters) - Moscow's claim that Russian air strikes in Syria had killed prominent Islamic State leader Abu Muhammad al-Adnani is false, U.S. defense officials told Reuters on Wednesday. "Russia's claim is a joke," one of the U.S. defense officials said, speaking on condition of anonymity. The Pentagon on Tuesday said it had targeted Adnani, who Islamic State has said was killed in Aleppo province. (Reporting by Phil Stewart; Writing by Yara Bayoumy)