Turkey has insisted that there was no ransom or quid pro quo that led to the terrorist group Islamic State releasing 49 Turkish hostages in Mosul, Iraq last week.  But President Recep Tayyip Erdogan hinted that there might have been a prisoner exchange.

Erdogan is in New York City for this week’s gathering of the United Nations General Assembly.  At a sideline appearance at the powerful Council of Foreign Relations think-tank, the Turkish leader remained vague on the details.

Islamic State abducted the 49 Turkish diplomats, soldiers, and civilians in June during the fall of Mosul.  They were back in Turkey this past weekend.

“This process that took 102 days involved an operation by the national intelligence agency,” said Erdogan, and that “It was a historic, very important process.”  He noted that Israel released 1,500 Palestinian prisoners in exchange for one Israeli hostage, and ended that sentence with, “So you see, it’s possible.”

Critics are very concerned about what Turkey might have promised Islamic State to obtain the release of the hostages.  Islamic State’s self-proclaimed “caliph” Abu Bakr al-Baghdadi reportedly said that the Turkish hostages were released “with the condition of Turkey not joining the Crusader alliance.”  Turkey in recent days has prevented scores of Kurdish youths to cross south over the border and join the fight to defend some Kurdish towns from an Islamic State advance. 

Turkey is a US ally and a member of NATO.  US Secretary of State John Kerry now says that he expects Turkey to join the fight against Islamic State, now that the 49 hostages are free.