Islamic State militants had seized nearly 700 hostages in Syria: Putin

President Vladimir Putin said on Thursday that Islamic State militants had seized nearly 700 hostages in part of Syria controlled by U.S.-backed forces and issued an ultimatum promising to execute 10 people every day.

Speaking in the Black Sea resort city of Sochi, Putin said the hostages included several U.S. and European nationals, adding that Islamic State was expanding its control in territory controlled by the U.S. and U.S.-backed forces.

Putin did not specify what the militants' demands were.