Russia's President Vladimir Putin and World War II veterans lay flowers at a war memorial during Putin's visit to the Crimean port of Sevastopol on May 9. Putin's visit to Crimea, which was annexed by Moscow in March, is a "flagrant violation" of Ukraine's sovereignty, authorities in Kiev said today. (ALEXEY DRUZHININ/AFP/Getty Images) #

Local people greet Russian President Vladimir Putin upon his arrival to Sevastopol, Crimea, May 9. Russian President Vladimir Putin arrived in Crimea, the peninsula annexed by Russia from Ukraine in March, to take part in celebrations marking the Soviet victory over Nazi Germany in World War II. (SERGEI ILNITSKY/EPA) #

A police station is ablaze in Mariupol, eastern Ukraine, May 9. Fighting between government forces and insurgents in Mariupol has left several people dead. (Evgeniy Maloletka/Associated Press) #

Pro-Russian women comfort each other while attending a pro-Russian rally during the commemoration of the Victory Day in Donetsk, Ukraine, May 9. Victory Day honors the armed forces and the millions who died in World War II. This year it comes as Russia is locked in the worst crisis with the West, over Ukraine, since the end of the Cold War. (Manu Brabo/Associated Press) #

Russian servicemen march during a military parade marking the 69th anniversary of the victory over the Nazi Germany in the WWII, in Sevastopol, Crimea, May 9. (ANTON PEDKO/EPA) #

A man jumps over a burning barricade outside the city hall in the southeastern port city of Mariupol, May 9. Ukrainian security forces killed about 20 pro-Russian rebels who tried to seize control of police headquarters in the eastern port city of Mariupol on Friday, the Interior Minister said. (Marko Djurica/Reuters) #

Ukraine's acting premier Arseniy Yatsenyuk (L) shaking hands with veterans during a ceremony marking Victory Day in Kiev on May 9. Russian President Vladimir Putin took a victory lap his first visit to Crimea since its annexation by Russia, as fighting in eastern Ukraine left at least 21 dead just days ahead of a separatist vote. The visit drew a sharp rebuke from authorities in Kiev, who accused the Russian strongman of stoking tensions with his visit to Sevastopol, home to Russia's Black Sea fleet. (ANDREW KRAVCHENKO/AFP/Getty Images) #

Fierce fighting between Ukrainian troops and pro-Russian rebels broke out in Mariupol, killing at least 21 people, all but one of them insurgents, according to the interior minister. An attempt by around 60 rebels armed with automatic weapons to storm the police headquarters turned into a "full-scale military clash." (GENYA SAVILOV/AFP/Getty Images) #

WWII veterans watch a military parade marking the 69th anniversary of the victory over the Nazi Germany in the WWII in Sevastopol, Crimea, May 9. (ANTON PEDKO/EPA) #

A boy walks in front of a WWII monument during a ceremony marking the Victory Day in the Ukrainian capital of Kiev on May 9. Ukraine's government on Friday protested Russian President Vladimir Putin's visit to annexed Crimea, where he inspected Russian naval forces in a commemoration of the Soviet victory in World War II. (SERGEI SUPINSKY/AFP/Getty Images) #

The inside of a police station which was attacked and burned on May 9, in Mariupol, Ukraine. Witnesses said that Ukrainian National Guard soldiers opened fire on police officers who refused orders to disperse a pro-Russia rally. (Brendan Hoffman/Getty Images) #

A policewoman uses her mobile phone as navy honor guards stand near of a World War Two memorial during celebrations to mark Victory Day in the Black Sea port of Odessa May 9. (Gleb Garanich/Reuters) #

A veteran from the Red Army sits surrounded by comrades while attending the commemoration of Victory Day in Donetsk, Ukraine, May 9. (Manu Brabo/Associated Press) #

A masked armed man stands guard outside the regional state building seized by pro-Russia separatists in the eastern Ukrainian city of Donetsk on May 9. (GENYA SAVILOV/AFP/Getty Images) #

People climb a broken armoured vehicle left behind after Ukrainian forces attacked police headquarters in an attempt to drive out pro-Russian militants in Mariupol May 9. (Marko Djurica /Reuters) #

Russian President Vladimir Putin (C), Russian Defense Minister Sergei Shoigu (R) and FSB (Federal Security Service) Chief Alexander Bortnikov (L) attend a military parade marking the 69th anniversary of the victory over the Nazi Germany in the WWII in Sevastopol, Crimea, May 9. (ALEXEY DRUGINYN / RIA NOVOSTI / KREMLIN POOL via EPA) #

Pro-Russian activists stand outside the regional Interior Ministry building in in Luhansk, eastern Ukraine. (Evgeniy Maloletka/Associated Press) #

People look at the covered dead body of a man after Ukrainian forces attacked a police headquarters in an attempt to drive out pro-Russian militants in Mariupol May 9. (Marko Djurica /Reuters) #

Armed pro-Russian militants sit with a young boy dressed also in military uniform, on top of an Armored Personnel Carrier (APC), during the Victory Day celebrations in Slaviansk, Ukraine, May 9. (ROMAN PILIPEY/EPA) #