Police and May Day demonstrators have clashed in Istanbul as crowds determined to defy a government ban tried to march to the city’s iconic Taksim Square. Security forces pushed back demonstrators using water cannons and tear gas. Protesters retaliated by throwing stones and hurling firecrackers at police. Istanbul’s police chief said around 136 people had been detained, according to private Dogan News Agency. Authorities have blocked the square that is symbolic as the center of protests in which 34 people were killed in 1977.