Authorities on Thursday detained 13 suspects and launched a manhunt for another in an investigation into a criminal gang that prosecutors claim was led by Istanbul’s former mayor, Ekrem Imamoğlu. Imamoğlu was arrested in 2025 and is currently on trial for allegedly running the gang, which prosecutors say thrived on bribery and corruption.

Thursday’s detentions focused on allegations of corruption in several tenders organized by the Istanbul Metropolitan Municipality (IBB), which was led by Imamoğlu of the opposition Republican People’s Party (CHP) between 2019 and March 2025. One tender allegedly tainted by corruption involved the acquisition of materials for İmamoğlu’s mayoral residence, according to investigators.

The suspects detained in the operation included former and current municipal staff. They include Mustafa Sökmen, head of the municipality’s department in charge of procuring materials for municipal services, and Rezzan Neslihan Vural, head of IBB’s financial services department.

The trial of the "Imamoğlu criminal gang” held its 74th hearing on Wednesday at the massive prison-courthouse complex where Imamoğlu and his alleged accomplices at IBB have been in custody since last year. A total of 407 people are defendants in the case.

An indictment against the defendants says Imamoğlu founded the gang in 2014, when he was mayor of Istanbul’s Beylikdüzü district, and that the gang was involved in 143 known offenses. The defendants are accused of causing losses to public coffers.

Imamoğlu’s associates named in the indictment include Murat Ongun, Fatih Keleş and Ertan Yıldız, municipal bureaucrats and advisers to Imamoğlu. Along with them, Adem Soytekin, a contractor who once worked for the İmamoğlu family’s construction business, is among the other defendants described by prosecutors as "senior members of the criminal gang.”

The indictment seeks a total prison sentence of between 849 years and 2,430 years and six months for Imamoğlu on charges including "forming an organization for the purpose of committing crimes,” "recording personal data,” "obtaining and disseminating personal data,” "concealing evidence of a crime,” "obstructing communications,” "damaging public property,” "bribery,” "publicly disseminating misleading information,” "extortion,” "fraud to the detriment of public institutions and organizations,” "laundering assets derived from crime,” "rigging public tenders,” "deliberate environmental pollution,” "violating the Tax Procedure Law,” "violating the Forestry Law,” and "violating the Mining Law.”

An indictment prepared against seven defendants, including İnan Güney, who was removed from his post as mayor of Beyoğlu, was also merged with this case.

The indictment seeks prison sentences ranging from nine years and eight months to 31 years and eight months for each of the seven defendants – Inan Güney, Ismail Akkaya, Seyhan Özcan, Veysel Eren Güven, Sabriye Akkaya, Mehmet Akif Bulut and Deniz Göleli – on charges of "aiding an organization established for the purpose of committing crimes without being a member of the organization” and "fraud to the detriment of public institutions and organizations.”

During the trial proceedings, 57 defendants, including those in the merged case, have been released, leaving 53 defendants in pretrial detention.

On Friday, the court is expected to announce its decision on whether to extend the defendants’ detention, although İmamoğlu is expected to remain in custody.

At the 74th hearing on Thursday, Serdal Taşkın, a defendant and former director of Kültür AŞ, an IBB subsidiary, responded to allegations of tender rigging. Taşkın said he served as director for 13 months and did not violate any tender regulations or laws. He denied allegations that he enriched himself through bribes in exchange for awarding tenders.