Turkish authorities have detained Istanbul Mayor Ekrem Imamoglu, a key rival to President Recep Tayyip Erdogan, as part of corruption and terror investigations, according to state broadcaster TRT, citing the Istanbul Prosecutor’s Office.

Turkey detained Istanbul Mayor Ekrem Imamoglu on Wednesday on charges such as graft and aiding a terrorist group, a step the main opposition party criticised as a "coup attempt against the next president".

Istanbul University has annulled Istanbul Mayor Ekrem Imamoglu's university diploma over irregularities with the Higher Education Board's (YOK) regulations, it said on Tuesday. The university's move came amid a government crackdown on opposition figures,