Army says three suspected ISIL fighters among hundreds of people detained while trying to cross border into Turkey.
The Turkey army has detained almost 800 people trying to cross the border from Syria.
The detainees include three suspected fighters from the Islamic State of Iraq and Levant (ISIL).
The three suspected ISIL members were sent to jail in the southern city of Sanliurfa after being detained separately on July 2, the military said.
Turkey has sent extra troops and equipment to strengthen parts of its 900km border as the risk of spillovers rises on suspicion of advances by both Syrian Kurdish forces and ISIL in northern Syria.
Turkey has maintained an open border policy throughout Syria's conflict, absorbing close to two million refugees, but requires legitimate refugees to pass through checkpoints and be documented.
Turkey has faced criticism from some Western nations for failing to do more to stop foreign fighters crossing out of the country and joining ISIL.