A group of OSCE observers being held in the eastern Ukrainian city of Slaviansk includes three German soldiers, a German translator, and military observers from the Czech Republic, Poland, Sweden and Denmark, a spokesman for the ministry in Berlin said.
Swedish Foreign Minister Carl Bildt wrote:
Extremely concerned with OSCE inspectors being abducted in Eastern Ukraine. Including one Swede. They must be released immediately.
More top news
'Vote Leave' - a cross-party campaign calling for Britain to leave the European Union in the forthcoming referendum - has been launched.
Sir Bruce Forsyth had to be rushed to hospital after a fall at his home.
Figures show seal shooting is on the decline but 51 licences were granted this year permitting the cull of more than 850 marine mammals.