KYIV -- Russia's main security agency has said it detained a Ukrainian employed by international cease-fire monitors, accusing him of spying on Kremlin-backed separatists in Ukraine's war-torn east.
The Federal Security Service said on July 18 that the man, Artem Shestakov, worked as an interpreter for the Special Monitoring Mission to Ukraine with the Organization for Security and Cooperation in Europe (OSCE).
The service, known as the FSB, charged that, while working in separatist-controlled territory in the eastern Luhansk region, Shestakov had collected intelligence information for the Security Service of Ukraine (SBU).
"Specifically, he divulged data on the movement of military equipment and manpower, the locations of military units and their commanders' telephone numbers to Kyiv," the FSB said.
The agency said that it detained Shestakov on Russian territory, though it didn't specify where or when. Аnd it said he had confessed to spying, including passing on information about Pavel Dryomov, a separatist Cossack leader in Luhansk who it claimed was killed by Ukrainian security services on December 12.
The agency said it later released Shestakov, and sent him back to Ukraine, because his activities did not undermine Russia's security.
Oleksandr Tkachuk, the SBU's chief of staff, told RFE/RL that the claims are "complete nonsense," and he said the fact that Shestakov was released "indirectly confirms his innocence."
Alexandra Taylor, an OSCE spokeswoman, would not confirm Shestakov was in fact the monitor in question, but said that the FSB report made it clear he was the person detained.
She said Shestakov was likely detained in the past three days while on leave.
The OSCE, which includes nations from North America to Europe to Central Asia, is tasked with monitoring the shaky cease-fire in eastern Ukraine's Donetsk and Luhansk regions, where pro-Russia separatists and Ukrainian government forces still engage in regular clashes.
The organization's daily reports on cease-fire violations are of great importance to Western leaders, many of whom say they will not consider lifting sanctions against Russia until the Minsk peace deal that Kyiv and Moscow agreed to is fully implemented.
Russia has long distrusted the OSCE, accusing it of bias. The organization's special monitoring mission includes observers from more than 45 countries, including Russia, as well as 305 Ukrainian staff.
"The Mission takes such allegations seriously; however, at this moment we have no evidence to support these claims," the OSCE said in a statement posted to Facebook.