ISTANBUL (AFP) - Dozens of Turkish nationals held hostage by Islamic State of Iraq and Syria (ISIS) jihadists in northern Iraq for more than three months have been released and brought to Turkey, Turkish Prime Minister Ahmet Davutoglu said on Saturday.

"Early in the morning our citizens were handed over to us and we brought them back into our country. At 5am they entered the country," Mr Davutoglu told reporters during an official visit to Azerbaijan, adding that all were in good health.

ISIS jihadists kidnapped 49 Turks, including diplomats, children and special forces from the Turkish consulate in Mosul on June 11 as they captured swathes of northern Iraq. The circumstances of their release were not immediately clear.

Mr Davutoglu said he was cutting short his Baku trip to meet the hostages in the southern Turkish city of Sanliurfa near the Syrian border.

Turkey, a Nato member and Washington's key ally in the region, has been reluctant to take part in combat operations against ISIS militants, or allow a United States-led coalition to use its air bases for strikes against the jihadists, citing its concern over for the safety of the hostages.