Law enforcement officers have launched a large-scale operation in Istanbul, and an arrest warrant has been issued for opposition mayor Ekrem Imamoglu, reports Sabah daily.

A large-scale corruption operation has been launched in the Istanbul Metropolitan Municipality, within the framework of which arrest warrants have been issued for Mayor Ekrem Imamoglu and his press advisor Murat Ongun.

Istanbul University decided on Monday to revoke Imamoglu’s diploma at the request of Turkey’s attorney general. This will prevent him from running for president.

Ekrem Imamoglu is currently the only candidate in the upcoming primary of Turkey's main opposition Republican People's Party (CHP), and he is considered the main opponent of current Turkish President Recep Tayyip Erdogan in the event of the latter’s re-nomination.

The Turkish constitution allows only people with higher education to run for president.