OSWIECIM, Poland (AP) — American civil rights activist the Rev. Jesse Jackson prayed and mourned at Auschwitz-Birkenau on Friday as he joined survivors paying homage to an often-forgotten genocide — that of the Roma people — on a key 75th anniversary.

In addition to the 6 million Jews killed in death camps such as Auschwitz, the Nazis killed other minorities during World War II, including between 250,000 and 500,000 Roma and Sinti.

Broadly speaking, Sinti are people who arrived from India and settled in Western and Central Europe many centuries ago, while Roma are centered largely in Eastern Europe. Since the term Gypsies is considered offensive, the groups are usually collectively referred to as Roma.

Jackson drew comparisons between the suffering of the long-persecuted minority in Europe with that of African Americans. In turn, a German Roma leader, Romani Rose, said the African American civil rights struggle that made vast achievements in the 20th century was a model and inspiration for his people, who still face marginalization and violence.

Bowing his head as he began a visit of the camp ahead of official ceremonies, the 77-year-old Jackson, a Baptist pastor, prayed that such horrors never occur again. He appeared deeply moved as he visited a surviving gas chamber and crematorium and toured an exhibition depicting the mass murder of Roma and Sinti.

During official ceremonies in front of a memorial to Sinti and Roma dead amid the ruins of gas chambers and barracks, Jackson warned diplomats and Roma from across Europe of the current dangers from a resurgence of racism and white nationalism.

"The ugly head of racism, nationalism and neo-Nazism is rearing up again in the U.S. and Europe," Jackson said. "It may be a mass murder at a church in Charleston, or neo-Nazis and racists chanting 'Jews will not replace us' in Charlottesville, or crowds demonizing our Congressional representatives today with chants of 'Send her back home!'"

That was what the crowd chanted at a recent rally by President Donald Trump after he hurled racist insults at Rep. Ilhan Omar and three other congresswoman of color.

The commemorations in southern Poland, which was under German occupation during World War II, fall exactly 75 years after thousands of the last remaining prisoners in the so-called Gypsy family camp at Auschwitz-Birkenau were killed.

Organizers said around 20 survivors, most of them Roma and Sinti but some Jewish, joined Friday's commemorations.

One survivor who spoke was Else Baker, who was sent alone at age 8 to Auschwitz after being labeled a "half-caste Gypsy" by the Nazi regime. Now nearly blind, she expressed gratitude to those gathered to mourn together before someone read out her speech for her.

She later said in England, where she has lived since the 1960s, "nobody has a clue" about what people like herself have witnessed.

During the war, members of the Roma community faced deportations, sterilizations and mass shootings in Soviet-occupied territories as well as the Nazi gas chambers. Many perished from starvation and disease.

Despite their immense suffering, it took decades for them to achieve even small measures of recognition.

It was only in 1982 that West German Chancellor Helmut Schmidt publicly declared that Sinti and Roma "were persecuted for reasons of race" and that "these crimes constituted an act of genocide."

More progress has come of late. In 2012, Germany erected a memorial in Berlin. Three years later, the European Parliament declared Aug. 2 to be "European Roma Holocaust Memorial Day."

And this year before International Roma Day on April 8, a bipartisan resolution was introduced in the U.S. Congress that said "Roma enrich the fabric of our nation" and that they have been "part of every wave of European migration to the United States since the colonial period."

U.S. Secretary of State Mike Pompeo called Friday "on all governments to take steps to combat intolerance against the Roma and to enable their full participation in civic and economic life."

Pope Francis has highlighted the discrimination that Roma still face today, even in Rome.

Asked how he felt about commemorations like the one Friday, 94-year-old French Roma survivor Raymond Gureme simply pressed his hand to his heart and bowed his head.

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