The main rival to Turkey’s President Recep Tayyip Erdogan has been formally arrested and charged with corruption. Ekrem Imamoglu, the mayor of Istanbul, was due to be selected as the Republican People’s Party’s (CHP) 2028 presidential nominee in a vote on Sunday. He has denied the allegations and said they are politically motivated. “I will never bow,” he wrote on X before he was remanded in custody. His detention sparked some of Turkey’s largest protests in more than a decade. Erdogan has condemned the demonstrations and accused the CHP of trying to “disturb the peace and polarise our people”. Imamoglu was one of more than 100 people, including other politicians, journalists and businessmen, detained as part of an investigation on Wednesday, triggering five consecutive nights of demonstrations. On Sunday, he was formally arrested and charged with “establishing and managing a criminal organisation, taking bribes, extortion, unlawfully recording personal data and rigging a tender”. He was remanded in custody pending trial. AFP and local media reported he had been taken to a prison in Silivri. Imamoglu has also been suspended from his post as mayor, Turkey’s interior ministry said in a statement.