Credit: AP
Istanbul's mayor, a popular opposition leader and key rival of President Recep Tayyip Erdogan, was arrested on Wednesday.
Several other prominent figures were also arrested, as part of investigations into alleged corruption and terror links.
The arrests are a dramatic escalation of a government crackdown on the opposition and dissenting voices in Turkey.
The state-run Anadolu Agency said prosecutors issued detention warrants for the mayor, Ekrem Imamoglu, and some 100 other people.
Istanbul Mayor and Republican People's Party candidate Ekrem Imamoglu during a campaign rally in 2024 Credit: AP
Among those detained was Imamoglu's close aide, Murat Ongun.
Authorities also closed several roads around Istanbul and banned demonstrations in the city for four days in an apparent effort to prevent protests following the arrest.
Critics say the crackdown follows significant losses by Erdogan's ruling party in local elections last year, amid growing calls for early national elections.
Government officials insist that the courts operate independently and reject claims that legal actions against opposition figures are politically motivated.
Security have cordoned off City Hall following the arrest of Istanbul Mayor Ekrem Imamoglu Credit: AP
"We are facing great tyranny, but I want you to know that I will not be discouraged," Imamoglu said earlier in the day in a video message posted on social media.
He accused the government of "usurping the will" of the people.
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