The de facto mayor of the Ukrainian city of Slaviansk has said mediators from the Organisation for Security and Cooperation in Europe who are seeking the release of a group of detained observers had arrived in the city.
The self-proclaimed mayor, Vyacheslav Ponomaryov, told reporters he was heading into talks with the mediators.
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His representatives said Cassidy, who was hospitalised last week, died "surrounded by those he loved."
The company’s recently appointed Chief Executive Dara Khosrowshahi said the breach was made by two individuals outside the company.