Czech riot police guard the Russian Embassy in Prague on April 18.
The Czech national unit to combat organized crime has detained at least five Czechs suspected of planning to travel to eastern Ukraine to fight alongside Russia-backed separatists against a backdrop of rising tensions between Prague and Moscow.
Investigators from the state prosecutor’s office suspect the five of preparing to join a militant group that calls itself the Donetsk People’s Republic, which opposes Kyiv and controls part of eastern Ukraine near the Russian border, Czech state prosecutor Martin Bily said on April 21.
Earlier reports suggested that around 20 people had been detained in the overnight operation by the NCOZ, a police unit to counter terrorism and extremism.
But Bily said five people had been detained and no one had been charged yet.
The roundup comes with the Czechs and Russians already embroiled in a flurry of diplomatic expulsions since the April 17 announcement that Czech authorities blame two Russian officers of a secretive GRU military intelligence unit for an explosion at an ammunition depot in 2014 that killed two Czech nationals.
The explosives that detonated in Vrbetice, in the southeastern part of the country, were purportedly part of a planned shipment via a Bulgarian businessman to supply Ukrainian forces fighting the separatists.
Prime Minister Andrej Babis rejected the label of "state terrorism" for the alleged Russian operation against his NATO-member state, triggering a national debate over relations with Russia.
But his government ordered the expulsion of 18 Russian diplomats, eliciting denials from Moscow and a bigger expulsion of Czech nationals by the Russian side.
Prague has since urged allies to carry out "collective action by EU and NATO countries aimed at solidarity expulsions" to support it in the ongoing dispute.
Czech reports said hundreds of police officers took part in the overnight operations on April 20-21 against the Czechs suspected of planning to fight in Ukraine, and some were said to be members of paramilitary groups.
The iDnes.cz news site said it wasn’t being ruled out that the suspects might have been in contact with some of the Russian diplomats, accused of being part of the military GRU directorate, who were targeted in the expulsions.
Kyiv and NATO have raised alarm bells this month over a buildup of Russian military forces near the border with Ukraine that threatens a new chapter in the simmering war since Russians invaded and annexed Crimea and began backing the separatists in Donetsk and Luhansk in early 2014.
Moscow has consistently rejected accusations that it is actively involved in the eastern Ukrainian conflict despite years of evidence to the contrary, including captures of Russian troops in the war zone.
Russian relations with the Czech Republic had already taken a public turn for the worse after local officials last year dismantled a statue in Prague dedicated to Soviet commander Marshal Ivan Konev.
Russia threatened a response and opened a criminal case over the slight.
With reporting by iDnes.cz, Respekt, and Aktualne.cz