Turkish police arrested 22 Syrian and Iraqi nationals in a series of raids over suspicions of their links to the Islamic State terrorist group, state news agency Anadolu reported.
The raids were conducted in the capital, Ankara, the report said. Seventeen Iraqis and five Syrians were held.
They fought for Islamic State in Syria and Iraq and had entered Turkey illegally, according to Anadolu. Security measures across the country are typically tightened ahead of Labour Day on Wednesday.
Last week, a suspected Islamic State member was detained in the north-western province of Tekirdag and accused of planning an attack on a World War I commemoration ceremony. Turkey was hit by a series of deadly attacks blamed on Islamic State since 2015, including a New Year's attack on 2017 at an Istanbul nightclub that killed 39 people.
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