A Polish MEP has refused to apologise after sharing an image on social media, depicting a herd of chained cattle wearing the striped prison uniforms of Nazi camps.
Sylwia Spurek, of the Progressive Alliance of Socialists and Democrats, tweeted the image to call for a "serious discussion" on animal welfare.
The post has sparked a severe backlash in Polish media and online.
A city councillor in Szczecin said the image was "spitting on the memory of the millions of Polish and Jewish victims of concentration camps".
The tweet was posted just days before the Holocaust Memorial Day on 27 January, which will mark the 75th anniversary of the liberation of Auschwitz-Birkenau.
The official Twitter account for the Auschwitz memorial and museum warned the MEP against the "instrumentalisation of the tragedy" of the Holocaust.
"Animal rights deserve a better and wiser defence than the trivialisation of horrible human suffering".
"This is beyond repulsive"
The founder of From the Depths, a Poland-based Holocaust commemoration and education group, has demanded that Sylwia Spurek issue a public apology to Holocaust survivors and their families.
"This is beyond repulsive," tweeted Jonny Daniels, adding that he has sent an open letter to the President of the European Parliament, David Sassoli.
In the letter, he called for "immediate action" against the "offensive, tasteless and hateful" tweet.
Jonny Daniels said he has "personally received multiple distressed calls from survivors of the Holocaust and their families", complaining about the image of the star-branded uniform.
Daniels also raised his concern over the "serious lack of Holocaust education and an extremely worrisome rise in antisemitism, especially in Europe".
Euronews has reached out to the European Parliament President for a response to this letter.
"I have been fighting anti-Semitism for years"
Following the criticism, Sylwia Spurek has defended her tweet and the image.
In a statement to the Jewish News, forwarded to Euronews, she said that she has been "fighting anti-Semitism, homophobia, xenophobia and racism for years".
"It is unfair to say that I could treat instrumentally people's enormous tragedy".
Sylwia Spurek is a former Deputy Commissioner for Human Rights in Poland and currently sits on the EU Committee on Civil Liberties, Justice and Home Affairs.
The MEP also argued the inspiration for the image was drawn from "letters of prisoners of concentration camps in which Jews compared their suffering to the suffering of animals".
The original image of the cattle, entitled "When will we ever learn", was created by Australian animal rights activist Jo Frederiks and is one of her many works that draws comparisons between the Holocaust and animal welfare.
"If we discuss the works of Jo Frederiks, let's also talk about her inspirations".