Turkish authorities have issued detention warrants for 24 suspects as part of an investigation into the so-called "public sector confidential structure” of the Gülenist Terror Group (FETÖ), prosecutors said Monday.

According to a statement from the Ankara Chief Public Prosecutor’s Office, the investigation was carried out by the anti-terrorism bureau and focused on operational phone lines allegedly used by members of the group within state institutions.

The authorities said coordinated efforts by the National Intelligence Organization (MIT) and counterterrorism police identified suspects who allegedly used ByLock, an encrypted messaging application used by members of the terrorist group.

Investigators also cited sequential calls made through pay phones and prepaid lines, a communication method prosecutors say is linked to the group.

The prosecutor’s office said evidence of organizational activity was obtained against the suspects, seven of whom are still employed in various public institutions.

Police launched simultaneous operations across 11 provinces centered in Ankara to detain the suspects, officials announced.

Separately, authorities in Gaziantep announced the capture of a fugitive convict wanted on charges of FETÖ membership.

In a statement shared by the Gaziantep Provincial Police Department on X, counterterrorism teams said the suspect was detained during an operation conducted under the coordination of prosecutors.

The individual had been sentenced to six years and three months in prison on terrorism-related charges and transferred to prison, the statement said.

The terrorist group orchestrated the July 15, 2016, coup attempt, which killed 252 people and wounded 2,734 others. Ankara also accuses FETÖ of being behind a long-running campaign to overthrow the state through the infiltration of Turkish institutions, particularly the military, police and judiciary.

Türkiye has targeted its active members and sleeper cells and its influence has been much reduced since 2016. However, the group maintains a vast network, including infiltrators suspected of still operating within Turkish institutions.