Clashes are continuing between police and anti-government protesters in the Ukrainian capital Kiev – prompting the president to warn that the violence is a threat to the whole country.A burnt-out line of buses and trucks in central Kiev marks the boundary between protesters and police.Clashes erupted on Sunday, after many more demonstrators rallied peacefully against President Viktor Yanukovych.The authorities say police have the right to use firearms in self-defence, reported the BBC. In a statement on Monday evening, President Yanukovych said that “now, when peaceful actions are turning into mass unrest, accompanied by riots and arson attacks, the use of violence, I am convinced that such phenomena are a threat not only to Kiev but to the whole of Ukraine”.Last week the president’s supporters in the Ukrainian parliament gave police extra powers to tackle demonstrators.At least 20 people have been arrested in the clashes, and about 100 injured, including dozens of police officers.