ZAGREB - The Nazi-hunting Simon Wiesenthal Centre has voiced outrage after a concert by a nationalist Croatian folk singer renowned for glorifying the country’s pro-Nazi World War II regime.

The Los Angeles-based organisation expressed "outrage and disgust in the wake of a massive show of fascist salutes, symbols and uniforms at a rock concert by popular ultra-nationalist Croatian singer Thompson," a statement said.

The concert, which took place in Zagreb on Sunday, was attended by some 60,000 people, among them officials including Education and Science Minister Dragan Primorac, it added.

Marko Perkovic, alias Thompson, is seen as an icon by Croatian nationalists and is supported by right-wing politicians.

He is known for sympathising with the 1940s pro-Nazi Ustasha regime at his concerts where, dressed in black, he gives a Hitler-style salute and shouts Ustasha slogans.

The Simon Wiesenthal Centre’s Israel director, Efraim Zuroff, called for the banning of concerts by singers who glorify fascism and racism.

"The time has come to prohibit public concerts by those who write songs of nostalgia for Jasenovac (concentration camp) and inspire the show of Ustasha symbols," Zuroff said in letter to Croatian President Stipe Mesic.

"I believe that only if someone of your stature and outstanding anti-fascist credentials will lead the efforts to combat this ugly wave of revived fascism, can this extremely dangerous new trend be stopped before it engulfs Croatia."

In the past, Perkovic has been known for his song "Jasenovac and Gradiska Stara," Croatia’s two notorious World War II concentration camps.

The song glorifies the Nazi-allied Ustasha regime and its leader, Ante Pavelic, and abuses Serbs.

According to local media reports, during Sunday’s concert Perkovic refrained from pro-Ustasha references and Hitler-style salutes.

Hundreds of thousands of Serbs, Jews, anti-fascist Croatians, Gypsies and others were killed by the Ustasha in the Croatian concentration camps.