Several people have been taken away in ambulances after being loaded onto stretchers, RT reports from Istanbul.
The crowd, which had been chanting: "Everywhere is Taksim, everywhere is resistance," was sent scrambling by the police, the latest escalation of tensions in more than two weeks of mass anti-government demos.
Turkish PM warns security forces will evict Istanbul park protesters
Turkish Prime Minister Tayyip Erdogan warned protesters occupying a central Istanbul park that they should leave before a ruling party rally on Sunday or face eviction by the security forces.
"We have our Istanbul rally tomorrow. I say it clearly: Taksim Square must be evacuated, otherwise this country's security forces know how to evacuate it," Erdogan told tens of thousands of supporters at a rally in the capital Ankar