Anadolu Agency says the suspects, including several Syrian nationals, were apprehended in simultaneous raids of homes early Thursday. The agency reports that police broke down doors with battering rams.
Turkey has suffered a series of deadly attacks blamed on IS militants, including a New Year's attack at an Istanbul nightclub by a gunman that killed 39 people.
The country is stepping up security measures ahead of the new year. Authorities have canceled several large-scale New Year's Eve street celebrations in Istanbul.