NEW YORK, NY.- Vandals sprayed antisemitic slogans and phrases denying the Holocaust in English and German on nine wooden barracks at the Auschwitz-Birkenau memorial site, in what officials there called “an outrageous attack on the symbol of one of the greatest tragedies in human history.”

Police in Oswiecim, a town in southern Poland where the concentration camp sits, said Wednesday they were analyzing footage taken by security cameras on the site and looking for anyone who could give them information about the vandals, who they believe struck between 8 a.m. and noon Tuesday. The barracks, which were defaced with black paint, housed men during the Holocaust and are near the Gate of Death in the Birkenau death camp. Police declined to give any further details about the slurs.

The Auschwitz Memorial site, in a statement published on its Twitter account, further condemned the graffiti as “an extremely painful blow to the memory of all the victims” who died at the camp.

More than 1.1 million people, the majority of them Jews, died in gas chambers at Auschwitz-Birkenau, or from starvation, cold and disease.

Countries across Europe have witnessed an increase in antisemitism online and among people protesting at demonstrations against the restrictions related to the coronavirus pandemic, with observers expressing concern that Jews increasingly feel unsafe in the European Union. The European Commission has earmarked 24 million euros (almost $28 million) to increase protection around synagogues and other Jewish events or sites.

Still, Jews who wear skullcaps in public in Germany report being harassed regularly. On Tuesday, a German-Jewish singer, Gil Ofarim, said in a video posted to social media that a hotel employee in the eastern city of Leipzig had told him to hide the Star of David pendant hanging from his neck if he wanted to check into his room.

The hotel involved, which is owned by the Marriott International hotel company, has expressed concern over the episode and placed two employees on leave pending the outcome of an investigation. But Jewish and political leaders across Germany expressed outrage over the issues the video raised, with many calling for more solidarity with Jews who are targeted.

“I hope that in the future we will encounter solidarity when we get attacked,” the head of the Central Council of Jews in Germany, Josef Schuster, said on Twitter, calling “the antisemitic hostility” against the singer “appalling.”

Officials at Auschwitz-Birkenau said their decision to not specify the wording of the slurs on the barracks, in an area of the camp where men were packed into crude wooden bunks, stacked three high from floor to ceiling, was a conscious effort to avoid spreading antisemitic hate any further.

“Because the intent of the perpetrator or perpetrators was to spread hate speech, we have decided not to make the images or the content of the graffiti public,” said Pawel Sawicki, a spokesperson for the Auschwitz-Birkenau Museum and Memorial, which preserves the site of the death camp.

Conservators will begin cleaning the damaged barracks once police complete their investigation, the museum said.

Antisemitic vandalism at the camp is rare, Sawicki said. Security is constantly being tightened, although the museum said that a plan to fully enclose the perimeter of the camp was part of a still-pending regional investment program.

More than a decade ago, a trio of thieves removed and made off with the notorious “Arbeit Macht Frei” (“Work Sets You Free”) sign that looms over the main entrance to Auschwitz. They were later arrested and the sign was recovered, but the theft led to an increase in funding to provide security for the camp, which the Nazis established during World War II in occupied territory that today belongs to Poland.

This article originally appeared in The New York Times.