Several Ukrainian opposition MPs have been injured in a brawl in the country's parliament, during which chairs were thrown.
They clashed with ruling Party of Regions MPs, who stormed the podium in the chamber on Thursday evening.
The supporters of the opposition leader and former prime minister, Yulia Tymoshenko, are now demanding a criminal inquiry into the incident.
Some MPs were admitted to hospital. Reports said some had fractures.
The clash came after a group of Mrs Tymoshenko's supporters had blocked the podium to protest at a corruption inquiry against her, which opened this week.
About 40 Party of Regions MPs, loyal to President Viktor Yanukovych, and 30 opposition MPs were involved in the punch-up, the Ukrayinska Pravda news website reported.
Correspondents say brawls are not unusual in the parliament, but this one was particularly violent.
Mrs Tymoshenko has been accused of misusing public funds. She has been told not to leave the capital, Kiev.
Mrs Tymoshenko, who lost power in March in a no-confidence vote, said the inquiry was politically motivated.
An auditors' report, published in October, alleged misuse of funds from the selling of carbon emission rights under the Kyoto protocol.
But Mrs Tymoshenko insisted that funds from the sales of Kyoto quotas, totalling 320m euros (£270m; $425m), had not been spent and were still at the disposal of the environment ministry.