Strongman Alexander Lukashenko demanded an explanation from Moscow on Wednesday after Belarus arrested Russian mercenaries allegedly plotting to destabilise the country ahead of next month's presidential election.
The surprise announcement is just the latest twist in an extraordinary election campaign that has seen the 65-year-old leader, who has dominated Belarus for nearly three decades, jail his key would-be rivals ahead of the vote.
"It is necessary to immediately turn to appropriate Russian structures so that they explain what is going on," Lukashenko told the head of the KGB security service at an emergency meeting.
Earlier in the day the Belarus security service arrested a group of 33 Russian fighters allegedly plotting to destabilize the country.
KGB chief Valery Vakulchik told Lukashenko that the detained men were members of the Wagner group, 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.
The arrests came less than two weeks before Belarus holds a tense presidential election on August 9, in which Lukashenko is seeking a sixth term, as public discontent builds over his policies.
Ahead of the polls, opposition protests have erupted across the ex-Soviet country of 9.5 million people, with a 37-year-old woman political novice, Svetlana Tikhanovskaya, quickly emerging as Lukashenko's main rival.
Lukashenko has accused some of his critics of being controlled by "puppeteers" in Moscow.
State news agency Belta said the authorities had received information about the arrival of 200 fighters in Belarus "to destabilize the situation during the election campaign."
Stacks of dollar bills
Belta said the detained men sported "military-style clothing" and carried heavy cases.
The state news agency also said the alleged militants gave themselves away because unlike ordinary 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," Belta said, adding that the men stayed at one of the country's sanatoriums.
National television showed several Russian passports that allegedly belong to the detained men, as well as stacks of dollar bills, packets of condoms and pieces of paper with Arabic script.
The men appeared to also have Sudanese pounds on them.
Some commentators suggested that the detained Russian fighters might have used Belarus as a transit point and were en route to Africa.
Unlike Russia, Belarus has kept its borders open during the coronavirus pandemic and operates flights as usual.
Russian author Zakhar Prilepin, who fought alongside Moscow-backed separatists in eastern Ukraine, said he knew some of the detained men.
"There are several fighters from our battalion," said Prilepin.
Prilepin said on Facebook that the fighters were probably en route to "some other destination," which Belarus "surely knows very well," suggesting that the detentions were a carefully-scripted affair.
The ex-Soviet country's security service has a history of exposing alleged foreign plots to destabilize the country before major elections.
The Russian Embassy in Minsk said it had been notified of the detention of 32 Russian nationals.
Russia is Minsk's closest political and economic ally but relations have been strained.
In recent years, Lukashenko has been under increasing pressure to inch closer to Russia but the Belarus leader has rejected the idea of outright unification with Moscow.
In a separate development, Belarus also arrested Vitali Shkliarov, a high-profile Washington-based strategist who has advised presidential candidates in the U.S., Russia and Ukraine.
Citing the security service, Belarussian television said Shkliarov had advised Tikhanovskaya's husband Sergei Tikhanovsky, one of Lukashenko's would-be rivals, who is now in jail.
"It seems that Belarus is heading into a period of extreme political flux," said Timothy Ash, a strategist at BlueBay Asset Management.
"Lukashenko has the fight of his life on in these elections," he said, adding that the detention of Russians might give the leader the excuse to either further clamp down on the opposition or cancel the election altogether.
Belarus officials said they were convening an emergency meeting of all election candidates on Thursday morning.