Suspects are accused of using the ByLock mobile app, an encrypted messaging app used by followers of Fetullah Gulen, who is believed to have orchestrated last year's attempted coup.
The Chief Public Prosecutor's Office in Istanbul on Thursday issued arrest warrants for 35 suspects linked to the Fetullah Terrorist Organisation's (FETO) media network, out of whom nine have been held so far, according to a judicial source.
The suspects, including the editor of the Birgun newspaper Burak Ekici, are accused of holding "membership in an armed terrorist organisation" and were involved in the media in one way or another. Nine of them are journalists
The suspects were believed to be users of ByLock, an encrypted messaging app the government says was used by the network of US-based cleric Fetullah Gulen.
Operations remain ongoing to apprehend the remaining suspects.
According to the government, FETO and its US-based leader Fetullah Gulen orchestrated the coup attempt of July 15, 2016, which left 250 people dead and nearly 2,200 injured.
Ankara also accuses FETO of being behind a long-running campaign to overthrow the state through the infiltration of Turkish institutions, particularly the military, police and judiciary.