One of the eight European observers being detained by pro-Russian separatists in the eastern Ukraine city of Slaviansk was escorted to an Organisation for Security and Cooperation in Europe (OSCE) vehicle and driven away.
The man was brought to the city administration by masked separatists and later walked out escorted by three unarmed men, got into a white OSCE jeep and drove off. The group declined to answer reporters' questions.
The observers, from Germany, Denmark, Poland and the Czech Republic as well as Sweden, were accused by their captors of spying for NATO and using the OSCE mission as a cover.
More top news
Through the day we'll see plenty of sunny spells but there will be a risk of showers too as they filter down from the northwest.
Pilots say they are rostered in 'illegally' and feel fatigued from working too many hours.
The alleged hacking follows reports of similar attacks on other Democratic organisations, amid fears of state-sponsored hacking.