Tens of thousands of Turks waving red national flags filled the streets of the Black Sea city of Samsun to protest against the Islamist-rooted government ahead of a July election.
The rally, the latest in a series of protests, was billed by organisers as a way of uniting the divided opposition against the government which they accuse of trying to undermine the secular state in overwhelmingly Muslim Turkey.
Prime Minister Tayyip Erdogan's ruling AK Party, which denies any Islamist agenda, has called a national election ahead of schedule to resolve a conflict with the secularist elite over a presidential election.
The secular establishment, including the military, judges and opposition parties, derailed the government's plan to elect Foreign Minister Abdullah Gul as president, fearing he might weaken the official separation of religion and state.
The latest protest follows a pact on Thursday between the main opposition Republican People's Party (CHP) and the smaller left-wing DSP to contest the 22 July election together.
There was a large police presence but a carnival atmosphere in Samsun, where modern Turkey's founder Mustafa Kemal Ataturk launched the country's war of independence in May 1919.
Police estimated attendance at 50,000 people, less than at similar rallies in Ankara and Istanbul. Around a million attended a protest in the Aegean city of Izmir last weekend.
