A high-ranking military officer and a lawyer who holds both Russian and Polish citizenship were charged with espionage in Poland on Friday. Both men were then sent to prison to await trial. Although prosecutors were reluctant to name which country the men were accused of spying for, Polish parliamentarian Marek Biernacki referred to the unidentified lieutenant-colonel and the Warsaw-based lawyer as "two agents of the Russian state."

"This was definitely a successful shot aimed at GRU," Biernacki added, using the common acronym for Russia's Main Intelligence Directorate.

The officer worked for the Polish Ministry of Defense, according to the country's Internal Security Agency (ABW). A military prosecutor clarified that the officer was indicted for "collaborating with a foreign intelligence service…and passing on sensitive information."

The men were arrested in simultaneous raids on Wednesday, but Prosecutor General Andrzej Seremet told the Polish news agency PAP that there was no proof the men were working in tandem.

Poland, a former Soviet satellite state whose relationship with Moscow has been a constant rollercoaster, is one of the most outspoken critics of Russia's actions in Ukraine. Warsaw has repeatedly called for tougher sanctions against Moscow and an increased NATO military presence in Eastern Europe as a counterbalance to Russia, specifically requesting a permanent deployment to Poland.

Poland has also openly supported Ukraine's new government, much to the Kremlin's chagrin.

es/slk (AFP, Reuters)