The demonstration, called by the main Kurdish BDP political party, was held at Taksim Square on the European side of Istanbul on the eve of a controversial referendum on constitutional changes.

Representatives of the protesters read a statement to the press denouncing the pressures of the Turkish government against the Kurds before the anti-riot police stepped in.

Three cars including a police vehicle were damaged when some protesters threw stones and hit the vehicles with bats, the news agency said. It did not indicate how many arrests were made.

The Kurdish protest came the day before a referendum to amend the country's constitution as proposed by the Islamist-rooted ruling AKP party. The changes aim to restructure the higher echelons of Turkey's judiciary, dominated by staunch secularists at loggerheads with the government.

Opinion polls suggest a neck-and-neck race in which last-minute sways of opinion will decide the outcome.

The BDP party has called on the country's Kurds to boycott the referendum vote.