Armed pro-Russian separatists have captured yet another Danish OSCE observer in eastern Ukraine, according to the government.

The trade and development minister, Mogens Jensen, confirmed that a Dane working for the OSCE observer mission in Ukraine had been taken and told Politiken newspaper that the detainment was “unacceptable”.

“We are talking about a civilian observer,” Jensen told Politiken. “The OSCE in Kiev is working on getting into contact with the detained observer and we are following developments very closely in the Foreign Ministry and at our embassy in Kiev.”

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A quick release?
A total of four observers disappeared on Monday afternoon. According to the BBC, the other three hail from Turkey, Switzerland and Estonia and are all civilians. The four were reportedly located in the border region between Donetsk and Lugansk when they seized.

“In the last few weeks there have been other instances of observers being detained for short periods of time and we hope that this group with the Danish observer will soon be released,” Jensen said.

Earlier this month a Danish OSCE member was detained by pro-Russian fighters in the eastern Ukrainian city of Slavjansk for more than a week before being released.

The area around the city of Donetsk has seen extensive fighting over the past few days. Dozens of pro-Russian fighters were reportedly killed as the Ukrainian army fought to regain control of the regional airport in Donetsk.