There have been rising tensions between Ukraine and Russia over access to the strategically important Sea of Azov.
Ukraine conflict
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Natalia Antelava tracks down the sister of a woman who was on board flight MH17 when it was shot down over Ukraine.
The Ukrainian military has given BBC News access to one of its Buks, to show how sophisticated a piece of military equipment it is.
Authorities evacuate about 12,000 people after explosions at the site to the north-east of Kiev.
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This comes after Ukraine accused Hungary of illegally issuing passports to Ukrainian citizens.
Read moreTom Burridge visits the sites central to the different theories about MH17's crash.
Why Ukrainian churches want to break free from Moscow
Ukrainian Orthodox churches have asked to become independent. They don't want to be part of the Russian Orthodox church any more. (Picture: Clergymen of the Ukrainian Orthodox church of the Kiev patriarchate take part in a ceremony. Credit: Reuters)
The head of the Russia-backed rebels in Donetsk, Alexander Zakharchenko, died in a bombing on Friday.
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The head of the pro-Russian rebels in Donetsk, Alexander Zakharchenko, is killed while at a cafe.
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Pro-Russian separatists were trying to take over observation posts, Ukraine's defence ministry says.
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