In 2018, the United States Department of State warned about "the glorification of the Ustasha regime and denial of the Holocaust" in Croatia, citing the placement of a plaque with the Ustasha-era salute 'Za dom spremni' on the grounds of a concentration camp memorial site, far-right rallies and the concert of the controversial band Thompson among other events. Efraim Zuroff of the Simon Wiesenthal Center describes Croatia as a "cradle of Holocaust distortion". Holocaust denial in Croatia typically involves the downplaying or denial of the Holocaust carried out by the Ustasha regime, particularly against Serbs and Jews at the Jasenovac concentration camp and it is done by public figures, though the regime's victims also included Roma and anti-fascist Croats. The Society for Research of the Threefold Jasenovac Camp in Croatia, an NGO with authors and academics among its members, claims that Jasenovac was a labour camp during World War II and that it was later used by Yugoslav Communists to imprison Ustasha members and regular Croatian Home Guard army troops until 1948, then alleged Stalinists until 1951. Following a series of book publications denying the Ustashe regime's crimes, the Simon Wiesenthal Center urged Croatian authorities in 2019 to ban such works, noting that they "would immediately be banned in Germany and Austria and rightfully so".