Bosnia's autonomous Serb entity is "fear-mongering" to undermine the country's integrity by organizing nationalist paramilitary groups and disproportionately arming the region's police, the national security minister said.
Secessionist pressures in the Serb Republic, set up as one of two autonomous regions as part of a 1995 deal to end Bosnia's war among Serbs, Bosniaks and Croats, is raising international concern about a relapse into turmoil in the Balkans.
Presidential and parliamentary elections will be held at federal and regional levels in October and Bosnian Serb authorities have already begun campaigning with steps some see as menacing to the country's fragile post-war equilibrium.
Under the 1990s peace accord meant to keep Bosnia intact, the country was divided into autonomous Serb and Bosniak-Croat entities with a relatively weak central presidency and government based in the capital Sarajevo.
National Security Minister Dragan Mektic accused the Bosnian Serb (RS) leadership of cranking up nationalist rhetoric and sponsoring paramilitary displays to intimidate opponents and sway voters ahead of the election.
Mektic is part of a moderate Serb bloc in the Sarajevo coalition government but is at odds with the RS nationalists under regional President Milorad Dodik.
"(RS) politics is verging on fear-mongering; there is an increased feeling of insecurity. All of this is making the security situation more complex," Mektic said in an interview with Reuters.
Serb, Russian paramilitaries
In January, a Serb far-right group, whose leaders were trained in Russia, marched in full combat gear during a parade in the Bosnian Serb regional capital Banja Luka and announced it would register as a charity there.
Mektic also cited what he called reliable reports that young Serbs have been undergoing military training at camps in Russia.
Russian motorcycle club Night Wolves, which is under U.S. sanctions for its role in a pro-Russian separatist insurgency in Ukraine, has announced a tour of the Serb Republic next week as part of a swing through the Balkans.
Mektic said such groups were believed to have been engaged by RS authorities to help inculcate intolerance of non-Serbs or moderate Serbs ahead of the October election.
"There are efforts to manipulate elections in different ways ... lately through the organization of special groups that exert a sort of physical pressure on (certain) citizens so that they feel endangered and do not come out to vote," said Mektic.
"This is especially practiced by Republika Srpska authorities ... They are trying to form a para-security structure under cover of a patriotic organization to use it in a showdown with opponents."
He said the Night Wolves were "no typical motorcycle club, they carry strong political messages ... The (RS) authorities want to give them legitimacy and use them in an election process," Mektic said, citing reports the Night Wolves planned to open an office in Banja Luka and monitor elections.
Mektic also said a recent purchase of 2,500 automatic rifles by RS police was legal but - echoing criticism from post-war international envoys in Bosnia - disproportionate compared with Bosnia's Bosniak-Croat Federation.
"They need weapons, this is not in dispute, but there is a question of proportion. It ... might bring about an unnecessary accumulation of weapons which may be misused in different ways."
Separately on Monday, a senior U.S. official visiting Kosovo's capital Pristina said Russia was playing "an increasingly destructive role in much of the Balkans in spreading disinformation and undermining democratic institutions."
U.S. Assistant Secretary of State for European and Eurasian Affairs Wess Mitchell, who is on a Balkan tour, added: "We have been clear in our conversations with the Russians that it's neither in their interest nor in the interest of the people in this region."
Western leaders have accused Russia, the Serbs' traditional big power ally, of seeking to exploit diminishing European Union leverage in the Balkans by manipulating political events. Russia denies such allegations.