A gunman attacked Sweden’s honorary consulate in the Turkish city of Izmir on Tuesday, leaving an employee of the diplomatic outpost wounded.

Turkey said it arrested the suspect and that the consular employee, a Turkish national, was taken to a nearby hospital.

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Turkish authorities said the assailant was mentally ill and refrained from elaborating on his possible motives. Sweden’s Ministry for Foreign Affairs said it’s in touch with the Consulate General in Istanbul, Turkey’s largest city.

The attack comes after public burnings of the Koran, Muslims’ holy book, in Sweden led to fury against the Nordic country across the Islamic world. The relationship between Turkey and Sweden has also been tense as Ankara initially vetoed Nordic expansion plans by the North Atlantic Treaty Organization before finally giving the green light in July.

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