By Simon Tomlinson and Matthew Blake Russia and Ukraine inched closer to war  yesterday after ‘many’ pro-Moscow separatists were killed during a major military offensive to seize back a rebel-held city. As fighting flared in the east of Ukraine, Vladimir Putin said the operation had ‘destroyed’ any hopes of peace. The Kremlin said Kiev’s decision to deploy the army against its own people was a ‘catastrophe’ and called for an emergency meeting of the United Nations Security Council. Scroll down for video As the fighting worsened, dozens of people had to be evacuated from a burning building in the Southern Port City of Odessa
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Day of intense fighting as army attempts to take back seized city Slaviansk
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Ukraine acting president said: 'Criminals received big losses during the operation: many were killed, wounded and arrested'
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Two helicopters shot down over Slaviansk, which was overrun by rebels
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One shot down by missile - killing its pilot and a serviceman - while the other forced to land under heavy attack
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Ukraine army arrested four suspected of bringing down helicopters
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Suspects heads covered in black bags and hands tied behind back
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Putin says the offensive 'effectively destroyed the last hope' of peace deal
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Phillip Hammond arrives in Lithuania to meet troops and Typhoon jets
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Meanwhile Russia deploys attack helicopters to borders with Baltic states
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Around 300 pro-Kremlin activists storm prosecutor's office in Donetsk
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Guard of 100 police officers attacked with rocks and Molotov cocktails
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Ukraine’s acting president Oleksandr Turchynov said the militants suffered ‘heavy losses’ in the anti-terror operation;
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Separatists shot down two army helicopters with missiles, killing both pilots;
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Women and children stood in front of Ukrainian tanks in protest at the offensive;
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Moscow said ‘English-speaking’ mercenaries were deployed against pro-Russian forces, claiming this proved US involvement in the mission;
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Military sources said Russia had deployed military helicopters to its border with Latvia and Estonia.
A pro Russian supporter is carried by his comrades after he was injured in running clashes with @placeholder in Odessa
Armed guard: A Ukrainian soldier looks on at a @placeholder checkpoint near the eastern town of Slaviansk - a city that has become the focus of the insurgency