A Cossack dances at the traditional Cossack games outside the village of Sengileyevskoye, south of Stavropol, Russia, September 27, 2014. Bosnia media reports that Nikolai Djakonov, who commanded an armed Cossack unit during Russia's takeover of Crimea earlier this year, was spotted in Republika Srpska, the Serbian entity of Bosnia, ahead of Cossack celebrations of Russian-Serb ties and the Oct. 12 general elections in Bosnia and Herzegovina. Reuters/Eduard Korniyenko

The appearance in Bosnia-Herzegovina of a Russian militia leader who helped Moscow annex Crimea has the tiny Balkan nation worried. Nikolai Djakonov, who earlier this year commanded an armed Cossack unit in Russia's takeover of Ukraine's Crimean territory, has arrived in the Serbian autonomous area of Bosnia known as Republika Srpska, according to the Guardian.

The putative reason for Kjakonov's arrival in Srpska is to participate in a war re-enactment that commemorates the Russian-Serb alliance during World War I. The re-enactment comes shortly before the Oct. 12 general election in which Milorad Dodik, a pro-Russian Bosnian-Serb, is tipped to win re-election as president. Russians clad in traditional Cossack costumes appeared Thursday in Banja Luka, the largest city in Srpska with a population of about 200,000.

Djakonov’s presence at a pro-Russian display has raised concerns that this might be the start of a push toward splitting the Serbian territory away from Bosnia. Dodik has said numerous times he supports independence for Srpska, something that could re-open wounds from the 1992-95 war that cost 100,000 lives. Cossack units sided with the Serbs responsible for the mass killing of Bosnian Muslims during that conflict.

According to the Guardian, Dodik might be doing some grandstanding of his own.

“Dodik has no interest in an independent [Republika Srpska],” Sead Numanovic, a Sarajevo journalist, told the British paper. “Serbia has no interest and will not support it, Russia is far away.”

But journalist Slobodan Vaskovic told the Associated Press on Friday the Cossacks -- who say they're just artists -- may have been brought into the country to cause trouble should Dodik lose the election.

Asim Mujkic, political analyst and professor at Sarajevo University, told Xinhua news agency earlier this week that he doesn’t expect any radical changes coming from the Oct. 12 elections. Bosnia-Herzegovina is led by three presidents representing three constituent peoples, Bosniaks, Serbs and Croats.