Bulgaria has accused two Russian diplomats of espionage and ordered them to leave the country within 72 hours.
State prosecutors launched a case against the two on the basis of a request from the State Agency for National Security (SANS), which alleges they collected state secret information with the intention of providing it to a foreign government.
The cases were suspended under the Vienna conventions on diplomatic immunity.
'Bulgaria's Foreign Ministry has declared two Russian diplomats 'personae non gratae' and has informed the Russian embassy with a diplomatic note,' a ministry spokesman said.
Russia did not immediately comment on the cases.
Their actions in question reportedly took place between 2016 and the present and include seeking to obtain plans on the Bulgarian military's modernization plans and technical preparedness.
Bulgaria is a NATO member with generally good ties with Russia, which supplies it with much of its energy.
Prosecutors said the two tried to recruit Bulgarian nationals with access to sensitive information, and in some cases promised financial compensation.
Bulgarian officials believe they wanted to provide that information to Russian military intelligence.
It is not the first spying case to have marred Sofia's relations with Moscow this year.
Two Russian diplomats were also declared personae non gratae in January for allegedly pursuing classified information on Bulgaria's electoral architecture.
Sofia also declined to grant a visa to a Russian defense attache choice in December 2019.
With reporting by Reuters
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