An Istanbul court has ordered the arrest of four of the 12 suspects, including Samayolu TV’s head, who were detained in a Dec. 14 police operation on media groups linked to U.S.-based Islamic scholar Fethullah Gülen.

Eight suspects, including Zaman Editor-in-Chief Ekrem Dumanlı, have been released. The court, however, slapped a travel ban on Dumanlı.

The four people arrested by the court are Samanyolu Media Group head Hidayet Karaca; Tufan Ergüder, the former head of the Istanbul Police Department’s anti-terror branch and the former head of the Hakkari Police Department; Ertan Erçıktı, the head of Police Security Branch office, as well as Police Chief Mustafa Kılıçarslan.

Karaca was arrested on charges of founding a terrorist organization while the other three were charged with being a member of the organization, reports said.

The interrogation of 12 suspects was completed by Istanbul 1st Criminal Court of Peace, with judge Bekir Altun saying the verdict would be announced at 2 p.m.

Four people were released by the court after the prosecutor asked for their probation