The United States on Tuesday urged Bosnia and Herzegovina to investigate reports of glorification of war criminals during banned ceremonies of Republika Srpska Day and incidents targeting returnees to towns from which non-Serbs were expelled.

“We urge competent authorities to investigate these incidents without delay and to hold the responsible individuals accountable,” a State Department spokesperson said in a statement.

“The United States is deeply concerned over reports of hate speech, glorification of war criminals and provocative incidents targeting returnees in the Republika Srpska entity over the weekend,” the spokesperson said.

Republika Srpska authorities organised a parade in Banja Luka on Sunday to mark 9 January as Republika Srpska Day. The date is a public holiday in the Bosnian Serb entity even though it has been declared unconstitutional. The Serb member of Bosnia and Herzegovina’s tripartite presidency, Milorad Dodik, said on this occasion that Republika Srpska is a state.

The parade involved members of Bosnian Serb police forces, and was attended by Chinese and Russian diplomats and government officials from Serbia.

On Monday, the European Union strongly condemned the negative and inflammatory rhetoric used by Republika Srpska leaders, making it clear it was ready to impose sanctions.

The US imposed sanctions on Dodik last month.

Bosnia and Herzegovina is going through the worst crisis since the end of the war in the mid-1990s after Bosnian Serbs blocked the work of state authorities and members of the Republika Srpska parliament voted in favour of their entity withdrawing from state institutions.