Bosnian Serbs celebrate an unlawful festival amid tensions.

The country’s Serbs celebrated an outlawed holiday Sunday with a provocative parade showcasing armored vehicles, police helicopters, and law enforcement officers with rifles marching in lockstep and singing a nationalist song, amid Bosnia’s worst political crisis since the end of its 1992-95 interethnic war.

Milorad Dodik, the de-facto leader of the Serb-run part of Bosnia and Herzegovina, spoke to tens of thousands of people gathered in Banja Luka, the de-facto capital of the Serb-run part of the country, and slammed the sanctions imposed by Washington last week on him for alleged corruption and threats to tear the country apart.

“This assembly is the finest answer to those who deny us our rights and continue to impose sanctions,” Dodik added.

“It proves to me that I must listen to you,” he continued, “that you did not elect me to fulfill the wishes of Americans, but to fulfill the wishes of Serb people.”

The Jan. 9 festival commemorates the date in 1992 when Bosnian Serbs declared their independence from Bosnia and Herzegovina, triggering the multi-ethnic country’s horrific, nearly 4-year-long conflict that became a byword for ethnic cleansing and genocide.

Bosnia’s top court prohibited the celebration in 2015, ruling that the date, which coincides with a Serb Christian Orthodox religious holiday, discriminates against Bosnia’s other ethnic groups – Muslim Bosniaks and Catholic Croats.

Bosniaks and Croats were persecuted and nearly expelled from the now Serb-controlled half of Bosnia during the war that killed 100,000 people and forced half of the country’s population to flee.

Following the war, Bosnia was divided into two semi-autonomous governing entities: Republika Srpska and one dominated by Bosniaks and Croats, under the terms of the Dayton peace agreement brokered by the United States.

Each section has its own government, parliament, and police, but the two are connected by state-wide institutions such as the judiciary, army, security agencies, and tax administration. All national activities require the agreement of all three ethnic groups.

Dodik has long advocated for the separation of Bosnia’s Serb mini-state from the rest of the country and its incorporation into Serbia.

He stepped up his separatist campaign this winter, promising to create a purely Serb army, judicial, and tax system. Bosniaks, he said, were “second-class citizens” and “treacherous converts” who “sold their original (Orthodox Christian) faith for food.”

Earlier in the day, Bosnian Serb officials took part in Serb Christian Orthodox ceremonies in the city’s main church, which were broadcast live on local television, while a special police unit marched in the parade singing a song about defending the Orthodox Christian cross and “the shiny new Serb Republic.”

Despite the fact that the festival has been forbidden by the Supreme Court, it is nonetheless celebrated every year, and the United States and the European Union have continually criticized it.

On Sunday, however, key officials from neighboring Serbia, including Prime Minister Ana Brnabic and Parliament Speaker Ivica Dacic; Russian and Chinese diplomats in Bosnia; and numerous representatives from France’s far-right National Rally party, joined the march and other celebrations.

In recent months, Dodik, a fervent pro-Russian, has expressed confidence that the Serbs’ “real friends” — Russia, China, and the European Union’s proponents of illiberal democracy — will serve as a bulwark against the “tyranny” of Western democracies.