Residents of the eastern Ukrainian city of Donetsk fled an area near rebel headquarters following shelling while cars with rebel gunmen rushed through the streets, two Reuters reporters at the scene said on Tuesday.
Cars with gunmen sped through red lights and shops closed early because of shelling, the Reuters reporters said.
Meanwhile, Russian President Vladimir Putin will take part in meetings with the European Union, and Ukraine leaders in Minsk on August 26, his spokesman said on Tuesday.
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The spokesman, Dmitry Peskov, said leaders of Belarus and Kazakhstan, who are part of the Russia-led Customs Union, will also be present.
"(The leaders) will discuss the relations between Ukraine and the Customs Union and there will be a number of bilateral meetings," Peskov said.
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—By Reuters with CNBC.