The clashes over the controversial plans to build the gold and copper mine left 26 people hurt, among them one seriously injured, the reports said.
According to CNN Turk, some 2,000 protesters turned out for a demonstration called by a local environmental group.
Clashes erupted when protesters, among them many women, tried to break through a barricade leading to the Cerattepe hill some 12 kilometres (seven miles) away from the town, where the mining project is located, NTV channel said.
The conglomerate behind the project is the Cengiz Holding company. Its chief executive is the tycoon Mehmet Cengiz, who is seen as a close ally of Turkish President Recep Tayyip Erdogan.
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Yesterday, Prime Minister Ahmet Davutoglu said the plans did not pose any danger to the environment, and warned against "all provocation" by protesters.
Environmental organisations have branded the planned mine "illegal".
The plan for the mine had initially been blocked by the Turkish judiciary, but it was finally approved after environmental impact reports gave the go-ahead to the project.
Erdogan and the Turkish government are very wary of environmentally-motivated protests after grassroots demonstrations in 2013 against the redevelopment of Gezi Park in Istanbul's Taksim Square snowballed into an uprising against his rule.