At least 13 people including teachers and company executives were detained as part of an investigation into the Gulen movement on Friday.
Police carried out operations in Ordu, Şanlıurfa, Kahramanmaraş, Ankara, Karaman and İzmir to detain 21 people with outstanding detention warrants.
The detainees are accused of having used ByLock, a smartphone app that Turkish prosecutors claim to be the top communication tool among Gulen followers.
The movement is accused of masterminding the July 15 coup while there is no court verdict handed down to this effect. Yet, Turkish law enforcement have so far detained some 120,000 people over links to the movement so far.