Pepe the Frog’s beginnings were unoffensive: he is the creation of comic book creator Matt Furie, who featured the frog as a character in the series Boy’s Club beginning in 2005. The character subsequently became a beloved meme, often called the “sad frog meme” and shared with a speech bubble reading “Feels good man” or “Feels bad man.” It was at times posted on social media by the likes of Katy Perry and Nicki Minaj.

But recently, as the Daily Beast reported in May, the character has been co-opted by a faction of Internet denizens who decided to reclaim it from the mainstream, and began sharing it in anti-Semitic contexts.

Anti-Defamation League: Pepe the Frog officially a "hate symbol" https://t.co/jky5XkXUJw pic.twitter.com/odancmgQP6

— The Daily Beast (@thedailybeast) September 27, 2016

“Images of the frog, variously portrayed with a Hitler-like moustache, wearing a yarmulke or a Klan hood, have proliferated in recent weeks in hateful messages aimed at Jewish and other users on Twitter,” the ADL wrote in a statement. “Once again, racists and haters have taken a popular Internet meme and twisted it for their own purposes of spreading bigotry and harassing users,” wrote ADL CEO Jonathan A. Greenblatt.

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Earlier this year, the ADL added the (((echo))) symbol to its Hate on Display database, noting that members of the alt-right movement were using it to single out Jewish users, particularly journalists, on social media.

This story was originally published on Time.com.