Turkish police on Wednesday arrested Istanbul mayor Ekrem Imamoğlu, a key rival of President Recep Tayyip Erdoğan, state-run media reported, as part of an investigation into alleged corruption and terror links.
The state-run Anadolu Agency reported that prosecutors also issued warrants for 100 other people. Authorities closed several roads around Istanbul and banned demonstrations in the city for four days in an apparent effort to prevent protests following the arrest.
Imamoğlu posted a video on Wednesday morning apparently reacting to the move, with the caption “A blow to the will of the nation”.
Imamoğlu, 53, “was detained and is now at police headquarters” a press aide told Agence France-Presse. The aide did not have permission to speak to the media so asked not to be named.
At the same time, Netblocks internet observatory said Turkey had restricted access to multiple social media platforms including X, YouTube, Instagram and TikTok.
The main opposition Republican People’s Party (CHP) is scheduled to hold a primary election on 23 March, at which Imamoğlu was expected to be chosen as its presidential candidate. The next presidential vote is scheduled for 2028, but early elections are likely.
“We are facing great tyranny, but I want you to know that I will not be discouraged,” Imamoğlu said earlier on Wednesday in a video message posted on social media. He accused the government of “usurping the will” of the people.
CHP’s chairman,Özgür Özel, denounced Imamoğlu’s detention as a “coup”.
“Currently, there is a power in place to prevent the nation from determining the next president,” he said. “We are facing an attempted coup against our next president.”
The arrest followed a search of Imamoğlu’s home on Tuesday, which came a day after a university invalidated his diploma, in effect disqualifying the popular opposition figure from running in the next presidential race. Having a university degree is a prerequisite for running in elections under Turkish law.
Istanbul University nullified Imamoğlu’s diploma, citing alleged irregularities in his 1990 transfer from a private university in northern Cyprus to its faculty of business administration. He called the university’s decision “illegal”, insisting it does not have the authority to cancel the diploma. The university’s move has been widely perceived as politically motivated.
“The days when those who made this decision will be held accountable before history and justice are near. The march of our people, who are thirsty for justice, law, and democracy, cannot be stopped,” he wrote on X.
He later also suggested the decision was made under pressure from Erdoğan’s government and raised concerns about the judiciary’s independence. He said that he planned to challenge the decision.
“What will I do next? I will keep running like a lion. There’s no stepping back, I’ll run even harder,” Imamoğlu said.

Wolfango Piccoli, of the Teneo political risk advisory firm, said the diploma’s annulment indicates that Erdoğan recognises he cannot secure an election victory.
“The decision to revoke Imamoğlu’s diploma goes beyond merely undermining a fair electoral race by removing the strongest opponent,” Piccoli wrote in an emailed note. “It reflects the boldness and power to dictate what is real and what is not by controlling the state apparatus.”
Imamoğlu has faced a series of legal challenges. In 2022, he was convicted of insulting members of Turkey’s Supreme Electoral Council in a case that could result in a political ban. He is appealing against his conviction.
He faces multiple other lawsuits, including allegations of trying to influence a judicial expert investigating opposition-led municipalities. The cases could result in prison sentences and a political ban.
He was elected mayor of Turkey’s largest city in March 2019 in a historic blow to Erdoğan and the president’s Justice and Development party, which had controlled Istanbul for a quarter-century. The party pushed to void the municipal election results in the city of 16 million, alleging irregularities.
The challenge resulted in a repeat of the election a few months later, which Imamoğlu also won. The mayor retained his seat following local elections last year, during which his party made significant gains against Erdoğan’s governing party.