Six suspects including four police officers were detained Tuesday in Ankara as part of a probe into the installation of spyware on several computers of the Department of Intelligence of Turkey's General Directorate of Security by police officers linked to the alleged Gülenist Terror Organization (FETÖ) through a software company in 2013.

The probe was launched by the public prosecutor's office after spyware was found on computer systems suspected to have been installed there by police officers removed from duty after the Gülen-linked December 17 and 25 police and judiciary operations. A software company in Istanbul is suspected to have involved with the spyware.

Newly-appointed officers detected the spyware and disabled it, preventing a possible leak. Following identity detection, an operation was launched and the suspects were detained.

Turkish authorities are probing the shadowy Gülen Movement for aiming to topple the government through judicial operations launched by its cadres using fake evidence and illegal wiretapping.

The movement is also being accused of forming a criminal organization in Turkey's police and judiciary through the infiltration of state institutions and bureaucracy through nepotism and large-scale cheating on nationwide exams.