Associated Press
Turkish Prime Minister Ahmet Davutoglu, center right, stands with freed hostages at the airport in Ankara, Turkey, Saturday, Sept. 20, 2014. Dozens of Turkish hostages seized by Islamic militants in Iraq three months ago were freed and safely returned to Turkey on Saturday ending Turkey’s most serious hostage crisis. The 49 hostages were captured from the Turkish Consulate in Mosul, Iraq on June 11, when the Islamic State group overran the city in its surge to seize large swaths of Iraq and Syria.

ANKARA, Turkey — The Turkish government won't reveal details of a covert operation that ensured the release of 49 people held hostage by the Islamic State group, President Recep Tayyip Erdogan said Sunday.

The hostages — 46 Turks and three Iraqis — were returned to Turkey on Saturday after more than three months in the hands of the Islamic State group, which captured them when it overran the Iraqi city of Mosul in June.

"There are things we cannot talk about," Erdogan told a group consisting of some of the hostages and their families. "To run the state is not like running a grocery store. We have to protect sensitive issues. If you don't, there would be a price to pay."

What Turkey did or did not promise to the Islamic State group has been a subject of speculation since even before the the hostages were released. Many observers expressed disbelief that the ruthless militant group would have relinquished such a big bargaining chip without getting something in return.

In comments to journalists made later in the day, Erdogan denied having paid a ransom, although he was far less categorical when asked whether the government had swapped prisoners with the terror group.

"Whether there was or wasn't a swap — 49 personnel were returned to Turkey," Erdogan said. "I would not exchange that for anything."

Serhat Guvenc, a professor of international relations at Kadir Has University in Istanbul, warned against reading too much into that particular hint.

"There's a thick fog around this issue," he said.

Raphael Satter in Istanbul contributed to this report.