President Zoran Milanovic on Friday abruptly cancelled his attendance at a ceremony commemorating the 28th anniversary of a military operation in the 1991-95 war held in the coastal city of Zadar after he had learned that two other people attending the ceremony had showed up wearing far-right insignia of the World War II Ustasha regime.

President’s spokesman, Nikola Jelic, told state news agency Hina that Milanovic arrived in Zadar for the ceremony on Friday morning. After “it was noticed that among the participants in the event were people wearing Ustasha insignia and (words) of the Ustasha salute,” Jelic said that Milanovic phoned Prime Minister Andrej Plenkovic to tell him that “this is unacceptable.”

“Since it was later established that persons wearing clothes with Ustasha symbols, including the Ustasha salute, would take part in the official part of the event, the President cancelled his attendance,” Jelic said. Acting on orders from President Milanovic, who is by law commander-in-chief of the armed forces, other active military commanders who came to Zadar, including armed forces’ chief-of-staff, Admiral Robert Hranj, also left the event after the first part of the ceremony, Jelic added.

Last year in May Milanovic also left a ceremony marking the anniversary of another wartime operation at Okucani in eastern Croatia, after some war veterans who attended the official part of the event wore t-shirts reading “Za Dom Spremni” (eng. “For Home(land) Ready”), the controversial Ustasha salute used in the Nazi-allied Independent State of Croatia (NDH) during World War II and also used by some far-right paramilitary groups during the 1991-95 war.

Although neither Milanovic nor Jelic specified who they were referring to, local media reports attributed the scandal to war veterans of the far-right paramilitary group HOS which took part in the 1991-95 war, who are known for wearing all black uniforms and whose logo contains the controversial salute.