Tensions are increasing in Ukraine after the president Viktor Yanukovych fled the country. Mr Yanukovych left by helicopter in the middle of the night after weeks of street protests calling for his resignation. Thousands of protestors fought bloody battles in the capital, Kiev. Scores of people died, many shot by riot police. The protestors wanted economic reforms and closer ties with the European Union. The east of the country did not see such levels of violence. Most people there voted for Yanukovych and lean more towards Russia than the EU.
The USA said it no longer considers Mr Yanukovych to be Ukraine's president. It warned Russia not to get involved in Ukrainian affairs, saying: "We strongly support Ukraine's territorial integrity and sovereignty." Fears are that Ukraine could break in two. Pro-Russian separatists are becoming more active, especially in the region of Crimea. Armed gunmen in Russian uniforms were guarding Crimea's main airport on Friday. Ukraine's acting president warned Russia against "military aggression" after Russia sent 150,000 troops to the Ukrainian border.