Al-Issa’s outreach to Jewish organizations also coincides with a broader alignment of interests and ties emerging between the Arab Gulf states and Israel, which share a common foe in Iran.

WARSAW, Poland (AP) — Muslim religious leaders joined members of a US Jewish group at Auschwitz on Thursday for what organizers described as “the most senior Islamic leadership delegation” to visit the site of a Nazi German death camp.

The interfaith visit came four days before the 75th anniversary of the camp’s January 27, 1945, liberation by Soviet forces and as world leaders gathered in Jerusalem to commemorate the Holocaust.

The secretary general of the Muslim World League, Mohammad bin Abdulkarim Al-Issa, and the CEO of the American Jewish Committee, David Harris, led the tour to the Auschwitz-Birkenau memorial in Poland.

The Nazis operated extermination and concentration camps in Poland when Germany occupied the country during World War II.

The American Jewish Committee said that Al-Issa, who is based in Mecca, Saudi Arabia, led a delegation of 62 Muslims, including 25 prominent religious leaders, from some 28 countries during the “groundbreaking” visit.

At one point, they prayed with their heads pressed on the ground at Birkenau, the largest part of the camp and the most notorious site of Germany’s mass murder of European Jews.

The AJC delegation included members of the organization, among them children of Holocaust survivors.

“To be here, among the children of Holocaust survivors and members of the Jewish and Islamic communities, is both a sacred duty and a profound honor,” Al-Issa said.

“The unconscionable crimes to which we bear witness today are truly crimes against humanity. That is to say, a violation of us all, an affront to all of God’s children.”

Auschwitz was the most notorious in a system of death and concentration camps that Nazi Germany operated on territory it occupied across Europe.

In all, 1.1 million people were killed there, most of them Jews from across the continent.

The visit comes as Saudi Arabia works to be seen abroad as a moderate and modernizing country following decades of adherence to a hard-line interpretation of Islam known as Wahhabism.

The Muslim World League, under al-Issa’s leadership, has embraced the effort.

Crown Prince Mohammed bin Salman’s strategy to modernize the kingdom is aimed in part at attracting greater foreign investment and fostering a national Saudi identity that is not founded solely on conservative religious values.

Al-Issa’s outreach to Jewish organizations also coincides with a broader alignment of interests and ties emerging between the Arab Gulf states and Israel, which share a common foe in Iran.

On Friday, members of the delegation will visit the POLIN Museum of the History of Polish Jews in Warsaw and attend Muslim and Jewish religious services there.