Anti-vaxxers have long used GoFundMe to raise money to spread their dangerous message—but now the site is cutting them off, The Daily Beast has learned.

“Campaigns raising money to promote misinformation about vaccines violate GoFundMe’s terms of service and will be removed from the platform,” spokesman Bobby Whithorne told The Daily Beast.

“We are conducting a thorough review and will remove any campaigns currently on the platform.”

It’s the latest crackdown on fact-challenged activists who believe the medical establishment, the government, and the pharmaceutical industry are engaged in a conspiracy to hurt American children.

The U.S. anti-vax movement has been blamed for two outbreaks of measles that have infected some 300 people—mostly children—in New York and the Pacific Northwest.

Last week, the American Medical Association warned social-media giants, including Amazon, Facebook, Google, Pinterest, Twitter, and YouTube, that they were helping to amplify the propaganda and confuse parents.

But as The Daily Beast has previously reported, anti-vaxxers have also used sites like GoFundMe to underwrite their messaging campaigns.

Whithorne said such fundraisers were “extremely rare” and that the site had removed fewer than 10 campaigns so far.

The Daily Beast found fundraisers benefiting or promoted by anti-vaccination or “vaccine choice” groups brought in at least $170,000 in the last four years. They include:

Prominent anti-vax activist Larry Cook, who spent more money than anyone else boosting his message on Facebook and collected $79,900 on various GoFundMe campaigns.

A vaccine-exemption attorney’s legal defense fund, which raised $25,220, that was promoted by Health Freedom Idaho and Sarasota for Vaccine Choice.

Three campaigns promoted by A Voice for Choice’s Facebook page that raised $39,801.

Melissa Sullivan, executive vice president at Health Choice Connecticut, which raised $2,650 under its previous name, Vaccine Choice CT, said GoFundMe’s eviction was a “violation of the First Amendment” and suggested, without any supporting evidence, that the platform was “feeling pressure from Big Pharma.”

“Whether you believe it’s true or not, everyone is entitled to their opinion,” Sullivan said. “I would hope they would reconsider. This movement needs to be able to get funds in order to fight pharma giants like Merck and other vaccine manufacturers.”

The fundraising campaigns of Cook, who funded Facebook ads targeting women of child-bearing age in Washington state during the latest measles outbreak, appear to have been taken down earlier this week.

Cook, whose website contained a disclaimer that some donations might go to pay his “personal bills,” did not respond to The Daily Beast’s request for comment.

GoFundMe’s terms of service explicitly ban donations toward “products that make health claims that have not been approved or verified by the applicable local… or national regulatory body.”

Earlier this week, it banned campaigns that raise money to cover treatment by a controversial German cancer clinic that offers unproven “high-dose vitamin infusions” and “ozone therapy” treatments. GoFundMe told the Financial Times it would be “speaking to organizations and experts” in the U.S. and the U.K. to fight medical misinformation.

“We know we have a major role to play in big issues like this, and as we continue to grow... our policies will continue to evolve to make sure we are best serving people,” a spokesman told the newspaper.

Tara Smith, professor of epidemiology at Kent State University, praised GoFundMe’s ban, but said she suspects the anti-vax movement will find other ways to raise money and spread its message.

“I appreciate the initiative, but [this movement] fundraised before GoFundMe and I’m sure they will find other ways after their campaigns are removed,” she said. “I suspect they will just go back to sending mailers or back to newsletters online to solicit donations in other ways.”

Smith said she was not surprised by the amount of money donated to anti-vaxxer groups through the site.

“There are a lot of true believers, and I know they’re willing to support that with their money,” she said “I just think of all the science that money could fund, and it makes me sad.”

In recent days, Facebook and YouTube announced efforts to reduce anti-vax content, and Amazon has started removing some books and documentaries. Now that GoFundMe has joined them, activists have started to look for new sources.

Sullivan, of Health Choice Connecticut, said her organization started a MeWe page in case Facebook boots it. In a post to more than 160,000 members in his private anti-vax Facebook group last week, Cook pitched a new idea that he claimed could “topple the vaccine industry”—an anti-vax media outlet.

“What if I created a website where parents—like you—could submit stories online that could be reviewed and easily published?... Like a natural parenting blog, only, with dozens or even hundreds of authors?” he wrote. “If done right, I think this could be a rapid deployment of stories to grab more attention… Get your stories ready NOW so that when we launch we can launch big.”