Jon Jafari, a popular YouTube host, sparked outrage this week after making controversial and false claims about immigration and race in the U.S.

Jafari, who goes by JonTron online, began the controversy by tweeting in defense of Rep. Steve King’s inflammatory statement that “We can’t restore our civilization with somebody else’s babies,” a comment that fellow Republicans and critics condemned as supporting white nationalism.

Jafari seemed to support King, tweeting: “Wow, how scandalous, Steve King doesn’t want his country invaded by people who have contempt for his culture and people! NAZI!!!”

He continued the defense during a two-hour conversation about immigration with Steven Bonnell, a streamer known online as Destiny. Throughout the debate, Jafari made a number of claims about race and immigration, including false assertions that minority communities are “turning everyone against each other.” When pressed by Bonnell to explain himself, Jafari repeatedly brought up concerns about the end of white populations in the U.S. Eventually, he said he could be open to the idea of immigration, saying: “If they assimilated, they would enter the gene pool, eventually.”

Bonnell told TIME he invited Jafari on to his show after he saw the tweet that appeared to support King because he likes debating political issues with people who have opinions that differ from his.

“I was surprised by how extreme he took things,” he said, noting that he was not trying to egg Jafari on. “Seemed like if you gave him a shovel, he would keep digging and digging.”

With more than 3 million subscribers on his YouTube channel, Jafari has long commanded a wide fanbase. Following Jafari’s debate with Bonnell, several JonTron fans expressed disappointment online.

“Jon argued that the most well off black man is somehow more violent or more likely to be a criminal than the worst off whites and that’s the end for me. I’m all for separating art and politics but I can’t support him when he openly spouts Stormfront talking points,” Reddit user johnlmonkey said, referring to the white nationalist website.

Reddit user EccentricOwl wrote: “I’m angry that someone I fell in love with would turn out like this. JonTron was the first “Youtube Personality” that I started to follow, and one of the first channels that I subscribed to. I wouldn’t call him a nazi or some sort of scumbag. He’s no Richard Spencer. But he’s okay with a guy like Richard Spencer, and that’s not okay with me.” Spencer is a white supremacist and president of the National Policy Institute.

The backlash has spilled over onto other YouTube channels under the NormalBoots group of shows, which includes the JonTron Show and others like DidYouKnowGaming and PeanutButterGamer.

Shane Gill, creator of DidYouKnowGaming, told TIME his channel has lost a “few hundred” subscribers since Jafari’s comments came to light. YouTube did not immediately respond to questions about changes in Jafari’s subscriber numbers.

“Several others from NormalBoots have also received online abuse since the Gizmodo article [posted Monday that covered Jafari’s comments] went live, since it implied Jon had influence over our content and audience. Up until that point, I believe no one who posts to NormalBoots.com (besides Jon) had experienced a backlash,” Gill said via email.

Jafari did not respond to TIME’s request for comment.

Get The Brief. Sign up to receive the top stories you need to know right now. Please enter a valid email address. Sign Up Now Check the box if you do not wish to receive promotional offers via email from TIME. You can unsubscribe at any time. By signing up you are agreeing to our Terms of Use and Privacy Policy . This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply. Thank you! For your security, we've sent a confirmation email to the address you entered. Click the link to confirm your subscription and begin receiving our newsletters. If you don't get the confirmation within 10 minutes, please check your spam folder.

Write to Mahita Gajanan at mahita.gajanan@time.com.