Turkish authorities uncover massive data breaches linked to Istanbul municipality

The Istanbul Chief Public Prosecutor’s Office has launched a sweeping investigation into what officials describe as a criminal network established under the auspices of Istanbul Mayor Ekrem İmamoğlu, uncovering massive breaches of personal data and unauthorized transfers abroad.

According to the findings, investigators identified the leak of personal and location data of 4.7 million users to two foreign countries via the “Istanbul Senin” mobile application. The probe further revealed the sale of personal and location data of 3.7 million users on the dark web, as well as the processing and leakage of electoral ballot-box information belonging to 11 million citizens through the “İBB Hanem” app, Caliber.Az reports, citing Turkish media.

In connection with the ongoing inquiry, arrest warrants were issued for four suspects — two employees from the municipality’s Smart City Planning Department and two from its Communication Coordination Center.

The suspects face charges of “unlawful dissemination of personal data” and “membership in a criminal organization.” During interrogations, investigators reportedly established the suspects’ links to the organization’s leadership and their direct involvement in the processing and transmission of data abroad.

The case has sent shockwaves through municipal and political circles, raising serious concerns about data security, governance, and the misuse of digital infrastructure within Istanbul’s administration. The investigation remains ongoing.

Istanbul Metropolitan Municipality (IBB) Mayor Ekrem Imamoglu was detained this March as part of an extensive investigation into the municipality, with police conducting searches at his residence.

The Istanbul Chief Public Prosecutor’s Office confirmed that a detention warrant had been issued for 100 individuals, including Imamoğlu, whom authorities have referred to as a "suspected criminal organisation leader".

Just a day before the raid, authorities annulled his university diploma, raising concerns among opposition supporters about the timing of the investigation.

By Vafa Guliyeva