A female school employee was killed and a female student wounded on Monday when a rocket believed to have been fired from Syria struck a school in southeastern Turkey, the local governor's office said.
Turkish army radar showed shots were fired into the border province of Kilis from Islamic State outposts inside Syria, military sources operating in the area told Reuters, adding that the army had retaliated "in kind".
The wounded student was taken into surgery. Two other rockets, also believed to have come from Syria, landed in an empty field next to the school, the governor's office said.
Footage broadcast on the website of the Hurriyet newspaper showed what appeared to be a body lying by the door of the school in Kilis town, the provincial capital, as shocked women and children were escorted from the building.
Kilis is on the edge of a roughly 100-km (60-mile) strip of Syrian border territory controlled by Islamic State. Turkish towns in the region have frequently seen artillery fire spill over during Syria's civil war, about to enter its sixth year. Turkey's armed forces have responded in kind.
As well as suffering spillover from the war, NATO member Turkey, part of the U.S.-led coalition against the Sunni radicals, has become a target for Islamic State. A suicide bombing last week in Istanbul, blamed on the group, killed 10 German tourists. Bombings in Ankara and the border town of Suruc last year killed more than 135 people.
Turkish tanks and artillery bombarded Islamic State positions in Syria and Iraq in the days after last Tuesday's bombing in Istanbul, killing almost 200 fighters, Prime Minister Ahmet Davutoglu said.
Ankara has been accused by some Western allies of waking up too late to the threat from Islamic State and allowing foreign fighters to cross its territory and join the group's ranks in the early stages of the conflict, something Turkey denies.