Protests erupted across multiple Turkish cities denouncing the arrest of the mayor of Istanbul even as President Recep Tayyip Erdogan issued a stern warning that demonstrations would not be tolerated.

Protests have raged on for a fourth night in Istanbul following the arrest of the city's mayor, part of the largest demonstrations Turkey has seen in more than a decade. Ekrem Imamoglu, a rival of Turkish President Recep Tayyip Erdogan, was detained on Wednesday, days before he was due to be selected as a 2028 presidential candidate.