Ofcom, the British communications regulator, announced on Monday it had issued imageboard 4chan a £20,000 ($26,000) fine for noncompliance with the Online Safety Act.

The fine — which will increase by £100 ($133) per day from Tuesday — is a small penalty by the standards of most commercial entities. However it marks the next escalatory step in a process that could ultimately see Ofcom require British internet service providers block access to the site.

Under the Online Safety Act, web platforms featuring user-generated content accessible from the United Kingdom have duties to protect users from harmful and illegal content.

Ofcom announced in January that online pornography sites would by July have to verify that all of their users were adults or potentially face being fined up to £18 million ($22.3 million) or 10% of their global turnover, whichever is higher, or even having their domains blocked by the country’s internet service providers.

Historically, 4chan has hosted some of the ugliest material on the web. The anonymous messaging board has been linked to the nonconsensual sharing of intimate images, as well as online harassment and racist agitation, much of which could fall foul of British laws. 

Some of it, however, is protected speech in the U.S. As previously reported by Recorded Future News, officials in Westminster are bracing for a clash with the White House as far-right social media platforms have dismissed legal requests from Ofcom tackling illegal online content.

U.S. tech companies were warned in August they could face action from the Federal Trade Commission for complying with the European Union and United Kingdom’s regulations about the content shared on their platforms.

That month, 4chan and Kiwi Farms — an online harassment hub — filed a lawsuit against the British government arguing its enforcement of the Online Safety Act was an infringement of their rights. The lawsuit states that both websites “while controversial, [operate] fully in compliance with the laws of the United States.”

Britain’s technology secretary, Liz Kendall, said: “The Online Safety Act is not just law, it’s a lifeline. Today we’ve seen it in action, holding platforms to account so we can protect people across the UK.

“Services can no longer ignore illegal content, like encouraging self-harm or suicide, circulating online which can devastate young lives and leaves families shattered,” she added.

“This fine is a clear warning to those who fail to remove illegal content or protect children from harmful material. We fully back the regulator in taking action against all platforms that do not protect users from the darkest corners of the internet.”