The sources who spoke on condition of anonymity said gendarmerie forces held 25 migrants in the northwestern Kirklareli province.

The migrants are Afghan, Pakistani and Syrian nationals. Two alleged human smugglers were arrested.

Separately in the central Anatolian Sivas province, police stopped a passenger bus for a routine control and held nine undocumented Afghan migrants, the sources added.

Moreover, police detained 74 undocumented migrants -- also Afghan, Pakistani and Syrian nationals -- in the western Aydin province, who were trying to go to Greece through illegal means.

A suspect was arrested and remanded in custody for human smuggling.

Another 113 migrants were held in Dikili and Bademli districts of western Izmir province.

Separately in western Manisa province, police rounded up 37 migrants from Pakistani origin. 

Turkey has been a main route for refugees trying to cross into Europe, especially since the beginning of the civil war in Syria.