Ukraine arrests official who doubled as Russia's spy

Ukraine's state security service (SSU) on Thursday arrested a government official they claim was doubling as an "agent of Russian intelligence." The official formed part of Prime Minister Volodymyr Groysman's inner circle, according to authorities.

"Together with the Security Service of Ukraine, an official in the government's secretariat was found to be working for a long time in the interests of the enemy state. He was detained," Groysman said in a post on Facebook.

Kremlin spokesman Dmitry Peskov said Russian authorities are aware of the arrest, "but we have no information," reported state-owned TASS news agency.

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Authorities did not provide a name or position for the suspect, but local media reported that Stanislav Yezhov, the premier's assistant, had been detained a day earlier.

Yezhov reportedly accompanied Groysman on all international trips during his time as assistant, and previously worked in the president's office and the Ukrainian embassy in the US. Ukraine's state security service said he had been recruited by Russia's Federal Security Service (FSB).

From intelligence partners to 'enemy'

In the wake of the Soviet Union's collapse in the early 1990s, Russia's FSB and its Ukrainian counterpart cooperated on security and counter-intelligence.

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However, all that changed in 2014, when Russian forces staged a military intervention on the Crimean Peninsula and held an internationally condemned referendum to annex the Ukrainian territory. In particular, the intelligence-sharing framework is believed to have collapsed as the SSU moved towards working with European partners.

The SSU had cultivated "partnership and cooperation agreements with their NATO counterparts" in the wake of the annexation, said Ukrainian analyst Maksym Bugriy of the Washington-based Jamestown Foundation.

Russia's illegal annexation of Crimea was seen as a response to pro-European protests in the capital Kyiv that toppled the government of former President Viktor Yanukovych, a staunch Kremlin ally. The annexation triggered an armed insurgency in eastern Ukraine, where pro-Russian rebels have demanded recognition as a separate, sovereign state.

ls/dm (Reuters, dpa)