Msgr. Ivo Tomasevic, secretary-general of the Sarajevo-based bishops' conference, told Catholic News Service the Mass in Sarajevo's Sacred Heart Cathedral, led by Cardinal Vinko Puljic, marked the 75th anniversary of the massacre of mostly ethnic Croatian internees sent back to what was then Yugoslavia from a camp in Bleiburg, Austria.

The annual Mass, held at Bleiburg since Yugoslavia's 1991 breakup, has been criticized by some European politicians for alleged far-right links, while Austrian bishops have urged the avoidance of nationalist slogans.

The Bosnian bishops' conference said Cardinal Puljic had agreed to host the May 16 Mass in Sarajevo after the COVID-19 pandemic made cross-border gatherings impossible.

"This was not a commemoration, but a holy Mass for people killed without trial and sentence," Msgr. Tomasevic told CNS June 1. He urged critics "to respect religious freedom, leave historians to research what happened, and show respect for the deceased, ensuring all victims and crimes are judged by the same criteria."

Croatians implicated in their country's Nazi-aligned wartime Ustasha regime fled to Austria with their families and army remnants to escape communist forces led by Josip Broz Tito. They asked the Allies, led by the British, to grant them temporary asylum, but the British sent them back to Yugoslavia after false assurances from Tito that they would not be harmed.

At least 70,000 men, women and children -- including Slovene and Montenegrin refugees -- were killed and dumped in mass graves, many of which are still being identified.

In a May 20 interview with Bosnia's Catholic Radio Marija, Cardinal Puljic said he had received personal threats in connection with the Mass, adding that his church had prayed "for all the victims, not for Ustashas or criminals."

Preaching on Pentecost May 31, the cardinal said "hate speech" remained "very present in Sarajevo," but added that he had also received messages of support from "many people who are not Catholics."

In his CNS interview, Msgr. Tomasevic said international representatives overseeing implementation of the Dayton Peace Accord, which ended the 1992-1995 Bosnian war, had recognized the right of religious communities to pray for "innocent war victims" and condemned threats to participants in the Sarajevo Mass.

"Whoever proclaims the Gospel of Christ knows every church prays for the dead and leaves judgment to God, trusting in God's mercy. A crime is always a crime, no matter who committed it," he said.