ISTANBUL

At least 52 people were arrested Tuesday as part of a probe into the information technology network of the Fetullah Terrorist Organization (FETO).

The suspects are among the 105 people -- including former employees of The Scientific and Technological Research Council of Turkey (TUBITAK), Presidency of Telecommunication and Communication (TIB), and Surat Information Technology Co. -- against which arrest warrants had been issued by the Istanbul chief public prosecutor's office, according to a police source who spoke on condition of anonymity due to restrictions on speaking to the media.

The suspects are accused of using the ByLock messaging app which is said to have been used by members of FETO during the July 15 coup attempt, the source said. They are also accused of attempting to provide technical support for the coup bid.

Operations are ongoing to arrest the remaining 53 suspects.

One month after the coup attempt, Turkey shut down TIB and transferred its responsibilities and staff to the Information and Communication Technologies Authority.

The TIB was supposed to be an independent regulatory body, but according to Turkish officials, the institution had become "a nest for moles" at the hands of members of Fetullah Terrorist Organization, an observation which President Recep Tayyip Erdogan had also voiced repeatedly in the previous years.

- Arrest warrants issued for former academics

In another probe into the staff of Turgut Ozal University which had been shut down in the aftermath of the coup attempt for alleged links to FETO, arrest warrants were issued for 40 people including former academics and other staff members, Ankara Chief Public Prosecutor’s Office said.

The former employees are accused of using the ByLock smartphone app, which is believed to have been cracked by Turkish security agencies months before the coup, allowing them to identify tens of thousands of apparent FETO supporters.

According to the Turkish government, the Fetullah Terrorist Organization (FETO) and its U.S.-based leader Fetullah Gulen orchestrated the defeated coup of July 15, 2016, which left 250 people martyred 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.

Reporting by Halil Demir and Baris Kilic; Writing by Sibel Ugurlu