Tech billionaire Elon Musk has visited the site of the Auschwitz death camp.
The visit comes after intense criticism of how X, formerly Twitter, tackles antisemitic posts and just weeks after Mr Musk apologised for endorsing an antisemitic conspiracy theory.
Prominent Jewish leaders called for Mr Musk to see for himself one of the most symbolic sites of the Holocaust.
Later he will address online antisemitism at a conference hosted by the European Jewish Association (EJA).
Nazi Germany murdered at least 1.1 million people in the Auschwitz death camp in occupied Poland during World War Two. Almost one million were Jews. The museum notes more than 200,000 were children and young people.
Mr Musk laid a wreath and participated in a memorial service, including lighting a candle, during a private visit to the site.
Photos showed him there with his son on his shoulders and standing next to Holocaust survivor Gidon Lev.
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As a result of the fall-out over Mr Musk's enthusiastic agreement with an antisemitic post, Apple, Disney and IBM paused ads on X.
In response, the entrepreneur has accused advertisers of attempting to "blackmail" him with money, and used expletive filled language to express his disdain for their actions.
The Tesla boss, who took over the platform in October 2022, faced accusations of antisemitism in November when he replied, "You have said the actual truth" to a post on X that made the false claim that Jewish communities push hatred against white people.
The White House immediately condemned his post, which drew anger online.
Mr Musk said the endorsement was a mistake, describing it as "one of the most foolish" things he had done on the platform.
Later in November Mr Musk joined Israeli Prime Minister Benjamin Netanyahu on a tour of the Kfar Aza kibbutz targeted by Hamas as part of the 7 October attacks in which 1,300 people were killed and about 240 taken back to Gaza as hostages.
Today, senior political figures from European countries and Mr Musk will meet in Krakow, Poland "to discuss and find solutions to the astronomical rises in antisemitism affecting Europe," the EJA said.
"This troubling trend" had been escalating since the war in Gaza, it said.
The Jewish Community of Oporto is a board member of European Jewish Association (EJA) and was represented by its director Dr. Michael Rothwell, whose grandparents died in Auschwitz.
During a live discussion broadcast on X in September, EJA chairman Rabbi Menachem Margolin invited Mr Musk to visit Auschwitz.
Rabbi Margolin said it would be "a very strong statement" and "could contribute a lot to Holocaust awareness and the struggle to combat antisemitism".
They were gassed, starved, worked to death and killed in medical experiments.
The Memorial and Museum Auschwitz-Birkenau has previously been critical of X.
In August, the museum criticised the platform after it had initially failed to remove a post denying the Holocaust, saying it did not break its rules.
The offensive post was a reply to one from the museum about a three-year-old Jewish girl murdered in the camp's gas chambers.
The post called her death a "fairy tale" and used antisemitic tropes.
According to a post on X by the museum, it had reported the offensive reply but received a response saying that after viewing the "available information" the platform had decided no rules had been broken.
That initial response to the museum's complaint, according to X, was down to a mistake during the first review - it was escalated and removed in a second review.
X's policies state that Holocaust denial is prohibited.
Shortly after publication of an article about the incident, a museum spokesperson told the BBC that moderation was vital in tackling antisemitism but there seemed to be "a problem on X in the quality of moderating and responding to reports".
But the Tesla boss has strongly defended his record in combating online hate.
In his discussion with Rabbi Margolin, Mr Musk said it was absurd that he was accused of antisemitism "when all the evidence points the other direction and my entire life story is in fact pro-semitic."
He previously threatened to file a suit against the Anti-Defamation League, a Jewish advocacy group, over its claims that problematic and racist speech has soared on the site since his takeover.
X is also currently suing non-profit Media Matters after it accused the site of allowing antisemitic posts next to advertising. X's lawsuit alleges it used "manipulated" data in an attempt to "destroy" the platform.
Source: BBC
