Turkish police detained 12 suspects on Friday as part of an expanding corruption investigation targeting alleged irregularities in municipal tenders linked to Istanbul’s opposition-run metropolitan municipality, prosecutors said.
The Istanbul Chief Public Prosecutor’s Office said the detentions were tied to an investigation into what authorities described as an "organized crime network” allegedly connected to Ekrem Imamoğlu who was suspended from his post as Istanbul metropolitan mayor and jailed.
According to prosecutors, investigators examined six tenders carried out by the municipality’s European Side Road Maintenance and Repair Directorate and the Electronic Systems Directorate under the municipality’s Information Technologies Department. Authorities alleged that the tenders were manipulated through a "fictional and irregular bidding system” designed to interfere with public procurement procedures.
Police carried out simultaneous raids in Istanbul, Kırklareli and Trabzon provinces, detaining 12 suspects. One additional suspect was found to be abroad, prosecutors said.
Among those detained were senior municipal officials, including a department head, branch managers, engineers, technicians and representatives of private construction companies allegedly involved in the tenders, according to Turkish media reports.
The suspects were taken to police headquarters for questioning.
The prosecutor’s office said the investigation focused on allegations of bid-rigging and misconduct in public tenders allegedly conducted under the authority of departments affiliated with the Istanbul Metropolitan Municipality (IBB).
The corruption investigation into was completed with the preparation of a 3,809-page indictment on Nov. 11, 2025.
In the indictment, former Mayor Imamoğlu is identified as the alleged "leader of a criminal organization” and is accused of several offenses, including establishing an organization for the purpose of committing crimes, bribery, laundering criminal proceeds, fraud involving public institutions and organizations, recording personal data, illegally obtaining and disseminating personal data, concealing criminal evidence, obstructing communications, damaging public property, receiving bribes, publicly spreading misleading information, extortion, laundering assets derived from crime and rigging tenders.
On the same day, authorities separately announced another operation targeting alleged bribery and permit irregularities in Istanbul’s main opposition Republican People’s Party (CHP)-run Üsküdar district municipality.
In that investigation, seven suspects were detained over accusations that municipal officials demanded financial benefits from contractors and intermediaries during occupancy permit and construction licensing procedures, prosecutors said.
Investigators alleged that officials identified irregularities in construction projects and then sought payments in exchange for approving permits. Authorities claimed the payments were made through cash transactions, company accounts and other financial channels.
The latest operation follows an earlier investigation launched in April into alleged bribery related to occupancy permits in the Uskudar municipality. During raids conducted in Istanbul and Yalova provinces on April 7, police detained 22 suspects, including Üsküdar Deputy Mayor Filiz Deveci and municipal company executive Nazım Akkoyunlu.
Nine suspects, including Deveci and Akkoyunlu, were later arrested pending trial, while others were released under judicial supervision.
As corruption investigations widened across Türkiye, police carried out an early morning operation on Friday targeting the CHP-run Merkezefendi Municipality in the western province of Denizli, detaining five people, including the deputy mayor.
Turkish authorities said the operation was part of an investigation into alleged corruption within the municipality.