Gunmen in eastern Ukraine have detained another group of international civilian observers, the Organization for Security and Cooperation in Europe (OSCE) said on Friday.

The new group - consisting of four observers and one Ukrainian translator - were stopped by armed men in Sievierodonetsk, 100 kilometres north of Luhansk at around 7 pm (1600 GMT) on Thursday.

The abduction brings to nine the number of people linked to the OSCE currently being held by the separatist forces. Another four OSCE observers went missing earlier this week in the neighbouring Donetsk region.

A separatist leader in Luhansk said earlier Friday that four observers have been freed after being detained Thursday. The OSCE did not comment on the claim.

Separatist leader Alexei Chmilenko told the Russian Interfax news agency that the observers had been held because they had entered the area without prior notification.

The earlier group of OSCE workers abducted - a Dane, Turk, Swiss and Estonian - were on a routine patrol east of Donetsk on Monday night, when contact was lost with them.

The self-declared mayor of the separatist stronghold of Sloviansk, Vyacheslav Ponomaryov, has said that the four had been detained by his men.

Donetsk and the neighbouring region of Luhansk voted this month to break away from Ukraine in a referenda that Ukraine and the international community denounced as illegitimate.

Meanwhile, talks are due on later Friday in Berlin between EU Energy Commissioner Guenther Oettinger and Russian and Ukrainian officials.

Mr. Oettinger called on Russia to offer a fair price to Ukraine, which is facing bankruptcy amid unpaid Russian energy bills.

“Prices in the EU range between 350 and 390 dollars per 1,000 cubic metres - that would be fair,” he told Germany’s Deutschlandfunk radio.

Ivan Grachyov, the chairman of the energy committee in the Russia’s lower house of parliament, said that the price could be set at roughly 380 dollars - “if all agreements are honoured,” he told the Russian Itar-Tass news agency.

Russia has upped the gas price for Ukraine to 485.5 dollars per 1,000 cubic metres and says it is set to turn off the taps for gas to Ukraine - and onward to the rest of Europe - if it does not soon receive back payments.

The Ukraine crisis has led the EU to step up work on varying its energy sources, amid concerns that Moscow has been quick to employ gas as a tool to pressure Kiev.

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