US warplanes have carried out their first air strikes on Islamic State (IS) targets in Syria after taking off from a Turkish base, starting a key new phase in the campaign against the jihadists.
A US drone had last week executed a single lethal air strike against an IS target in Syria but this was the first time on Wednesday that manned US fighter jets had carried out raids after taking off from Turkey's strategically-located Incirlik base.
Turkey is now pressing a two-pronged "anti-terror" offensive against IS jihadists in Syria and Kurdistan Workers' Party (PKK) militants in northern Iraq and southeast Turkey following a wave of attacks inside the country.
But until now the Turkish air strikes have overwhelmingly concentrated on the separatist Kurdish rebels, to the frustration of Western commentators who want to see Turkey ramp up its involvement in the fight against IS.
Using the Incirlik base outside the city of Adana in southern Turkey drastically cuts the distance needed for the US jets to fly to northern Syria compared with other launch bases further afield in the Middle East.
"Today, the United States began flying manned counter-ISIL missions from Incirlik Air Base, Turkey. Strikes were conducted," Pentagon spokeswoman Commander Elissa Smith said.
Turkey's Dogan news agency said three US fighter jets were seen taking off from Incirlik in the evening.
Last month, Turkey agreed to open up the base to coalition planes for bombing IS targets in Syria following months of tough negotiations.
The expectation now will be that Turkish forces - which so far have only carried out the most limited strikes against IS - will also join in the bombing raids.
"Turkey and the United States will co-ordinate operations," a Turkish official said on condition of anonymity in Ankara just before the Pentagon announcement.