The unidentified man says he was kidnapped after working as a freelance reporter in the region.
“Those who have to leave Syria are the ones who have not been permitted by the Syrian government,” said one of the top advisers to Iran’s supreme leader.
Information on the whereabouts of the bodies was provided by two high-level ISIS figures captured last month.
Trump’s figures have been disputed.
ISIS leader Abu Bakr al-Baghdadi once laid claim to half of Iraq and Syria, but now only a small, mostly desert stretch known as Al-Jazeera, or "the Island," remains.
Iranian supreme leader Ayatollah Ali Khamenei said, “The U.S. government is the cruelest and most merciless system in the world.”
“The actions of the U.S. coalition do not comply with legal norms. Beyond all doubt, it is an unprecedented act of aggression,” one Russian senator said.
Former Defense Secretary Chuck Hagel said the U.S. military “can’t fix the problems in Afghanistan” and Russia “really holds the cards” in Syria.
An account affiliated with Turkey’s so-called Operation Olive Branch claimed Kurdish fighters attacked the Free Syrian Army with chlorine gas.
Roman Filippov will be made Hero of Russia after his deadly standoff with the rebels.
As Kurdish forces attempt to defend their land from Turkey, Russia began the Sochi peace conference and its allies continued to gain ground.
As a Turkey-backed offensive neared Manbij, Syria, the head of U.S. Central Command said withdrawal was “not something we are looking into.”
“It is a strange incident,” Turkish media analyst Nate Schenkkan told Newsweek.
The White House said Trump had told his Turkish counterpart in a phone call to “limit its military actions.”
Neither Russian, Syrian nor U.S. forces have moved in to stop the Turkish invasion aimed at ousting Pentagon-backed Kurds from the enclave of Afrin.
China, Egypt, India, Iraq, Saudi Arabia, Sudan, Syria and Turkey were among those looking to get their hands on the S-400 missile defense system.
ISIS could be helped by a string of Turkish military strikes against Kurdish groups in northern Syria, U.S. Secretary of Defense James Mattis warned Tuesday.
After ISIS was mostly defeated in the east, the Syrian military set its sights on rebel-held Idlib, while Turkey targeted U.S.-backed Kurds in Afrin, Aleppo.
The government is advertising Aleppo and other Syrian cities at an event in Madrid.
Turkey and Syrian rebels have launched a joint operation against Syrian Kurdish forces, putting the U.S. and Russia in a difficult position.
China's long-term global economic and security goals fit in line with a victory for Syrian President Bashar al-Assad.