Police arrested four people on Monday, including Gültekin Avcı along with three police officers, on charges of perpetrating the case widely known by the public as "Selam Tevhid," in which prominent figures ranging from politicians to journalists were illegally wiretapped by members of the Gülenist Terror Organization (FETÖ) under the guise of an inquiry into the eponymous, nonexistent terrorist organization.

Avcı is a former prosecutor and lawyer who defends Hidayet Karaca, the general manager of the Samanyolu Media Group known to have ties with the Gülen Movement, who is being tried in another case. He is being accused of passing on Fethullah Gülen's instructions to members of the alleged organization and creating public opinion against the victims of the Selam Tevhid case.

Eight Gülen Movement-linked suspects were detained in Istanbul and İzmir on Friday after a court arrest warrant issue. Three police officers were released with the judicial control decision, following the completion of their investigations.

The Gülen Movement is accused of carrying out illegal wiretapping activities to allegedly oust the elected government. Its members are believed to have infiltrated government institutions such as the police and judiciary to be able to conduct operations against what it considers a foe. The movement is led by Fethullah Gülen, who lives in the United States in exile. The alleged controversial and shady activities by Gülenists have forced a slew of lawsuits to be filed against them.