Turkish fighter jets have entered Syrian airspace and launched a fresh attack on Islamic State targets - less than 24 hours after their first airborne attack on the militants.
More than 250 suspected terrorists were rounded up across the country earlier in the day.
Three F-16 jets were involved in the early morning strike which used laser-guided bombs launched from inside Turkish territory.
The attack was the first time Turkish planes have attacked the group.
Two IS headquarters and an "assembly point" were targeted near the village of Havar - but Syrian airspace was not violated, said a government official.
Tensions have increased over the past few days after IS militants fired at a Turkish border position in Kilis on Thursday, killing a soldier and wounding two others.
Turkish tanks returned fire, reportedly killing one militant.
President Recep Tayyip Erdogan said Turkey's strikes were the "first step" and that action against IS and Kurdish militant groups would continue.