German-Turkish author Doğan Akhanlı was detained in Spain on Aug. 19 after Turkey issued an Interpol warrant for the writer, Der Spiegel magazine reported.
Spanish police detained Akhanlı on Aug. 19 in the city of Granada, the weekly said.
Any country can issue an Interpol "red notice", but extradition by Spain would only follow if Ankara could convince Spanish courts it had a real case against him.
Akhanlı fled Turkey in 1991 and has lived and worked in the German city of Cologne since 1995.
Calls to the German foreign ministry regarding the detention of Akhanlı were not immediately returned.