Ukrainian opposition leaders have emerged from crisis talks with President Viktor Yanukovich saying he had failed to give concrete answers to their demands, and told their supporters on the streets to prepare for a police offensive.
Boxer-turned-politician Vitaly Klitschko told the thousands of protesters gathered on Kiev's Independence Square that during three hours of talks the president had given no clear response to their demands that the government be dismissed and sweeping anti-protest laws ditched.
Fifty people were detained overnight and 29 of them were officially charged with taking part in mass unrest, police said. A total of 167 police have been injured, officials said. There was no estimate of the number of civilians injured.
Ukraine has experienced difficult days before but few have been so complex or so pivotal.
The Ukrainian government says it is is ready to use all tools available to restore order if violence and unrest continues.
These are difficult days for Ukraine, a country edging toward its second revolution in a decade.