Ukrainian Prosecutor General Viktor Pshonka has called the events that occurred in central Kyiv on January 19-20 a crime against the state and a threat to national security, and called on opposition leaders to urge their supporters to leave Hrushevskoho Street.

"The mass disturbances accompanied by violence, arson, property damage, which basically pose a threat to Ukraine's national security, must stop immediately. This is not just hooliganism, this is a crime against the state. I am urging the opposition leaders: call your supporters off Hrushevskoho Street, explain the unacceptability of committing mass riots!" Pshonka said in a letter to organizers and participants of the protests, posted on Web site of the Prosecutor General's Office on Monday.