Tens of thousands of people gathered in Istanbul on Saturday to protest against the jailing of Mayor Ekrem Imamoglu, President Tayyip Erdogan's main rival, sustaining the largest demonstrations Turkey has seen in more than a decade. Hundreds of thousands have heeded opposition calls and taken to the streets nationwide since Imamoglu was detained last week and then jailed pending trial on graft charges. The main opposition Republican People's Party (CHP), other opposition parties, rights groups and Western powers have all said the case against Imamoglu is a politicised effort to eliminate a potential electoral threat to Erdogan.