WARSAW, Poland — Polish officials joined war veterans on Sunday to pay tribute to a World War II-era underground force that allegedly collaborated with Nazi German forces toward the end of the war in their battle against the Communists, who were imposing control on the nation.

A Mass in Warsaw opened ceremonies honoring the Holy Cross Mountains Brigade of the National Armed Forces on the 75th anniversary of its formation. The partisans were honored for their sacrifices to the fatherland.

“Mass was needed by the partisans, the soldiers who fought for the freedom of their homeland: Precisely to strengthen their decision to give everything, even their lives, for the freedom of their homeland,” Father Zbigniew Kępa, a military chaplain.

The priest said many soldiers and partisans during World War II drew their strength from the Eucharist.

President Andrzej Duda’s official patronage and the presence of ruling party officials underlined the right-wing government’s rehabilitation of a partisan unit that fought both Germans and Soviets and which is celebrated by the far right.

It is seen as a part of a broader attempt by the ruling Law and Justice party to appeal to right-wing voters ahead of the nation’s parliamentary vote in October.

Poland had a large underground Home Army under the command of a government-in-exile that never collaborated with the Germans, and remembrance ceremonies traditionally focus on those soldiers.

Although historians say the Holy Cross Mountains Brigade collaborated with the Nazis, a representative of the veterans, Jan Józef Kasprzyk, sought to deny such a link.

Kasprzyk described the claims of collaboration as a product of postwar communist propaganda meant to smear the unit’s legacy.

The official rehabilitation of the brigade began when Polish Prime Minister Mateusz Morawiecki honored its members at a cemetery in Munich in February 2018.

Morawiecki asserted at a news conference the same day that there were some “Jewish perpetrators” of the Holocaust.

The anniversary observances in Warsaw on Sunday were criticized by the children of Polish resistance fighters. Some wrote a letter to Duda saying, “Our fathers fought against the Nazis because they understood their duty toward their homeland. Any cooperation with the occupiers was unimaginable to them.”

Michael Schudrich, Poland’s chief rabbi, rejected an invitation to attend the remembrance ceremony, calling it “a personal insult.”

“Organizing these celebrations insults the memory of all Polish citizens who died in the fight against Germany,” he said.

Opponents of the commemorations held a protest where people held banners that said “No! to collaboration” and “Collaborating with the enemy is treason.”

Crux staff contributed to this report.

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