Turkey said Friday it had expelled more than 40,000 refugees living in Istanbul and sent them back to the provinces where they were initially registered.
A campaign was run from July through to the end of October, aimed at reducing the number of refugees in Turkey's biggest city and economic hub.
The country hosts some 3.6 million Syrian refugees -- more than any other country -- though technically they are only under "temporary protection" because the government does not offer them formal refugee status.
Under the system, they must stay in the province to which they were initially assigned, and can only visit other cities with short-term passes.
The Istanbul governor's office said 42,888 migrants were rounded up by police and sent back to their assigned provinces between July and October, without specifying their nationalities.
It said in July that 547,000 Syrians were officially registered in Istanbul, and that no new registrations were being accepted.
More From This Section
Turkey has faced limited social problems despite the refugee influx from the eight-year conflict in its southern neighbour.
But an economic downturn has sharpened tensions, and analysts say the refugee issue likely contributed to the ruling party's surprise defeat in the Istanbul mayoral election this year.
President Recep Tayyip Erdogan has sought to defuse the issue with plans to create a "safe zone" in northern Syria to which refugees can return, though rights groups have cast doubt on the feasibility of the plan.