Istanbul police have detained 62 foreigners suspected of having links to the "Islamic State of Iraq and Syria" (ISIS) in overnight raids, AFP reported Friday (December 1st).

Police have launched almost daily operations against ISIS cells across the country following concerns hundreds of alleged ISIS members have crossed into Turkey from Syria.

The suspects were detained during raids on 12 addresses in eight districts of Istanbul, the privately-owned news agency Dogan said.

They are suspected of providing financial support to fighters in "conflict zones", with the authorities opening deportation proceedings against them, it said.

Last month, Dogan said nearly 800 alleged ISIS members had illegally crossed into Turkey from Syria, though it did not say over what period.

Police detained 634 ISIS suspects last month, according to interior ministry figures.

There are concerns that those foreigners who have fought in Syria or Iraq will pose security risks on their return home as ISIS loses significant territory in Iraq and Syria.

At least 5,600 people, residents of 33 countries, have returned home, the Soufan Centre, a nonprofit security analysis group, said in October.