Wagner, Vagner Group mercenaries detained
Screenshot from the Belarus’s state-run news agency Belta shows Belarusian KGB agents arresting the alleged Russian mercenaries
Kyiv says it will seek the extradition of alleged contractors from the Russian private military company Vagner being held in Belarus as Moscow demanded their release, saying they were in transit and headed to Turkey.

Belarusian authorities have launched an investigation against 33 Russian contractors from Vagner who were detained earlier this week. Authorities allege they wanted to destabilize the country ahead of the August 9 presidential election.

Moscow has vehemently rejected Minsk's claims, with Kremlin spokesman Dmitry Peskov saying on July 31 that the 33 men were in transit to Istanbul before flying to "a third country."

"Their stay is connected neither to Belarus itself nor its internal affairs," Peskov told reporters, calling for their release.

However, Alyaksandr Agafonov, who leads the team of Belarusian investigators, later said on national TV that the men's plans for onward travel were just "an alibi."

He also said that their "evidence about the reasons for their stay in Belarus was incoherent and contradictory."

Meanwhile, the Ukrainian Prosecutor-General's Office said Kyiv would ask Belarus to hand over 28 of the detainees on charges of fighting alongside Russia-backed separatists in eastern Ukraine.

Nine Ukrainian citizens are among the 28, it said.

Fighting between Ukraine's armed forces and the separatists in the eastern Ukrainian regions of Donetsk and Luhansk has killed some 13,200 people since April 2014.

The Vagner Group is a Russian paramilitary organization believed to be run by Yevgeny Prigozhin, an influential Russian businessman close to President Vladimir Putin. Its fighters have turned up in conflicts in Ukraine, Syria, Libya, and Africa.

The chief of the Belarusian Security Council, Andrey Raukou, said on July 30 that "upwards of up to 200 militants" remain at large in Belarus and efforts to locate them continue.

The August 9 presidential vote is shaping up to be a tough race for incumbent Alyaksandr Lukashenka, an authoritarian leader who has been in power since 1994.

Lukashenka has cracked down on the opposition during the campaign, with the arrest of hundreds of people, including journalists, bloggers, and political activists. Charges were pressed against two potential candidates.

In a statement on July 30, Human Rights Watch (HRW) said that from May through July, Belarusian police arrested "at least 1,100 people for gathering peacefully on issues related to the election."

Nearly 200 people were sentenced to detention for up to 15 days and more than 300 others were fined, the New York-based human rights group said, urging the international community not to "ignore such serious flouting of human rights obligations."