The report, published this month by the Partnership for Working Families and the Action Center on Race and the Economy, found an array of children’s products on the site featuring imagery widely considered hateful. Arguably the most disturbing products included a baby onesie featuring a burning cross – a terroristic symbol of the Ku Klux Klan – and a children’s backpack featuring a cartoon frog wearing a Nazi SS officer’s cap. Others are more debatably objectionable, such as unofficial Lego-style figures modeled on German World War 2 soldiers.

The report also details a range of media sold by Amazon, particularly music and books, that it says promotes violence and racism. Those include dozens of books from the white nationalist publishing house Counter-Currents, self-published using Amazon’s platform and featuring titles like Truth, Justice, and a Nice White Country. One item is a children’s book by American Nazi Party founder George Lincoln Rockwell that appears intended to promote xenophobia.

Many of the items described in the report appear to violate Amazon’s own rules, which prohibit products that “promote or glorify hatred, violence, racial, sexual or religious intolerance or promote organizations with such views.” In a statement to Fortune, Amazon said in regard to non-book products that “Third-party sellers who use our Marketplace service must follow our guidelines and those who don’t are subject to swift action including potential removal of their account.“ Amazon’s guidelines on self-published books specifically state that pornography is unacceptable, but under “Offensive Content,” the guidelines only state that “what we deem offensive is probably about what you would expect.” Its guidelines for publishers are more detailed, but make no specific mention of hate speech.

As the report details, Amazon itself collects royalties of up to 40% of the sales price of media including books, and in some cases even more.

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Some of the items detailed in the report appear to have been recently removed, but many, including Rockwell’s children’s book, remain available at this writing. Other items still on the site display symbols recently adopted by white supremacists, including Pepe the Frog stickers and t-shirts, and flags for the “Republic of Kekistan” – Amazon even features one Kekistan flag as “Amazon’s Choice.” Amazon also sells rings, necklaces, and medals displaying the Iron Cross, a German military honor which predates the Nazi regime and remains in use by the modern German military, but retains associations with the Nazi era.

The report recommends that Amazon stop selling items bearing hate symbols, including books, and stop providing publishing and other services to known hate organizations. The sponsoring organizations are also promoting a petition to push for those changes.

That might seem like an easy ask, but the situation puts Amazon on the horns of a dilemma inherent to its business model, which allows almost any seller to list items on the site. Carrying white supremacist materials exposes Amazon to serious public relations risks, particularly as such groups are seen as increasingly influential and toxic to world politics. But removing offensive materials, particularly books, would itself expose Amazon to accusations of censorship or political bias.

The situation echoes similar quandaries that have roiled social media sites in recent years. Twitter, for instance, long touted its commitment to free-speech absolutism, but in 2016 began aggressively suspending or banning accounts associated with white supremacists, including for targeted abuse or promotion of violence. Those and similar platform bans have in turn become a rallying cry for the far right, who often both mask their positions and seek broader sympathy by positioning themselves as victims of censorship by digital platforms.

Update 7/7/2018: Updated to include a statement and guidelines provided by Amazon.