Clashes have erupted in Istanbul between May Day demonstrators and riot police as crowds tried to march to Taksim Square, disobeying a government ban.
Security forces pushed back demonstrators with water cannons and tear gas. Protesters retaliated by throwing stones and petrol bombs at police.
Taksim is symbolic for Turkey's labour movement. In 1977, 34 people were killed in the square during a May Day event when shots were fired into the crowd from a nearby building.