Turkish tanks crossed into Syria today after heavy shelling of an area held by Islamic State forces.
It came as Turkey again targeted IS in the Syrian border town of Jarablus after its foreign minister promised to “cleanse” the border.
Military sources said 70 targets in the area had been destroyed by artillery and rocket strikes, and 12 by air strikes.
Shelling began at about 2am UK time, with 224 rounds fired in the space of one hour and 45 minutes.
Turkish special forces are already inside Syria as part of the operation to clear IS out of Jarablus.
Turkey’s state-run news agency said tanks had crossed into Syria as part of the offensive. In its report, the Anadolu Agency, which cited unnamed military officials, did not say how many tanks entered Syria. The private NTV television said as many as 20 tanks had crossed into Syria and that clashes were taking place at the border.
Turkish counter-terror police also launched dawn raids on IS members in Istanbul today. Arrest warrants were issued before the operation, which included a raid on an address in the Pendik district on the Asian side of the city, according to reports.
A force of 1,500 Turkish-backed Syrian rebels is said to be waiting across the border to take part in the Jarablus operation.
The Turkish military has also shelled positions belonging to the Kurdish YPG militia, apparently to deter them from taking Jarablus themselves.
Ankara fears the Kurds could create an autonomous area near the border which could fuel Kurdish separatism.
After today’s offensive began, the Turkish prime minister’s office said: “The Turkish Armed Forces and the International Coalition Air Forces have launched a military operation aimed at clearing the district of Jarablus of the province of Aleppo from the terrorist organisation Daesh [IS].”
Turkey blames IS for a bomb attack that killed dozens of people in the south of the country at the weekend.
It had earlier ordered residents in the Turkish town of Karkamis — just across the border from Jarablus — to evacuate after the town was hit by mortar fire believed to come from IS positions.
Jarablus lies along the west bank of the Euphrates River, less than a mile from Turkey. It is the last major town held by IS on the border.
Turkey’s air strikes are its first inside Syria since the downing of a Russian jet in November. Moscow and Ankara only mended ties last month after punitive Russian sanctions.
Meanwhile, US Vice-President Joe Biden has arrived in Ankara, Turkey’s capital, where he is scheduled to meet with President Recep Tayyip Erdogan and Prime Minister Binali Yildirim.
