At least one person was killed as artillery shells hit close to the centre of Ukraine's separatist-held city of Donetsk for the first time.
It was not immediately clear if the artillery was fired by government or rebel forces.
Two shells landed 200 metres (660 feet) from the Park Inn Radisson, one of the city's main hotels, shattering windows.
Ukrainian troops have been slowly encircling Donetsk, the regional hub with a peace-time population of nearly a million.
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