Turkey's opposition party has urged supporters to take to the streets for peaceful demonstrations against the arrest of Istanbul’s mayor and top rival to President Recep Tayyip Erdogan. The plea on Friday came even as authorities widened a ban on protests. Ekrem Imamoglu was arrested this week over alleged corruption and terror links, escalating a crackdown on opposition figures and dissenting voices. Several other prominent figures were also detained. Many view the move as a politically driven attempt to remove a popular opposition figure from the next presidential race — a claim the government rejects. Thousands have gathered outside the city hall for rallies, and clashes have erupted between demonstrators and police elsewhere.