Hundreds of Turkish forces in armoured vehicles have entered war-torn northern Syria to evacuate troops guarding a historic tomb, demolishing it and moving the remains to a different site.
The remains of Suleyman Shah, who died in the 13th Century, were moved to a site in Syria closer to the border.
Turkey considered the shrine sovereign territory.
Islamic State (IS) militants in the area had threatened to attack it last year.
The government of Syrian President Bashar al-Assad, which has lost control over much of northern Syria as a result of the country's civil war, condemned the incursion as "flagrant aggression".
It said that Turkey had informed its Istanbul consulate about the operation but had not waited for Syria's consent.