Members of the Wagner group were allegedly plotting to destabilise the country ahead of next month's presidential election, Belta state news agency has reported.
Belarus has detained 33 Russian nationals it said were members of a Russian group of private military contractors, Wagner, after 200 members of the group entered the country.
"Thirty-two militants from foreign private military company Wagner were detained" near the capital Minsk, Belta state news agency said on Wednesday, adding that another Russian citizen was also detained at a separate location.
Belta also published a list of the names, surnames, and dates of birth of the alleged Russian mercenaries.
Russia's embassy in Belarus said it was seeking information from Minsk about the detentions, the RIA news agency reported.
The announcement came less than two weeks before Belarus holds a tense presidential election on August 9, in which President Alexander Lukashenko is seeking a sixth term despite growing discontent.
In the run-up to the vote, Lukashenko has jailed his top election rivals and accused some critics of being in cahoots with Russia.
Militants planned to 'destabilise' country
Belta said the authorities had received information that 200 militants had arrived in Belarus "to destabilise the situation during the election campaign."
The state news agency did not explain where the remaining suspected militants were.
They sported "military-style clothing" and carried heavy cases, the news agency added.
Belta also said the alleged militants gave themselves away because unlike Russian tourists, they did not drink.
"They did not consume alcohol or visit entertainment venues, they kept to themselves in order not to attract attention," the news agency said.
The men stayed at one of the country's health resorts where they "carefully studied" the area, Belta added.
Belarusian television showed several Russian passports that allegedly belong to the detained men.
Strained ties with Russia
Russia is the ex-Soviet country's closest political and economic ally but relations have been strained at times.
In recent, years Lukashenko has been under increasing pressure to inch closer to Russia but the 65-year-old leader has rejected the idea of outright unification with Moscow.
The Wagner Group is a shadowy private military firm that is reportedly controlled by an ally of Russian President Vladimir Putin and promotes Moscow's interests in Ukraine, Syria, and Libya.
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