Riot police in the Ukrainian capital, Kiev, have forcefully dispersed hundreds of protesters, beating some with truncheons, witnesses say.
It followed fresh rallies against President Viktor Yanukovych's refusal to sign an EU association agreement.
More than 1,000 people, most of them students, were in the square when police moved in, activists said.
"It was horrible. We were holding a peaceful demonstration and they attacked us," said protester Lada Tromada.
"They threw us away like garbage."