A far-right organization that had videos retweeted by President Donald Trump was one of several white nationalist Twitter accounts suspended Monday.

Trump caused controversy in November after he retweeted anti-Muslim videos originally posted on Twitter by the organization Britain First. The U.S. leader was criticized by the U.K. Prime Minister Theresa May who said he was wrong to retweet the posts.

In an email to its members Monday, Britain First described the Twitter suspension as a censorship of right-wing views.

“Twitter is now only available to those on the ‘left’ of politics. This latest attack on our movement demonstrates that ‘free speech’ is only available to those who do not criticize socialism or Islam,” the statement said.

The email stated that the main account of Britain First as well as that of co-leaders Paul Golding and Jayda Fransen had been suspended.

In a blog post published Monday, Twitter said it was enforcing new rules about hateful conduct and abusive behavior. The social media company said the new rules have taken immediate effect.

The post stated that company policy against abusive behavior had been widened to help prohibit “promoting violence against or directly attacking or threatening other people on the basis of their group characteristics.”

The accounts of American Renaissance, a white nationalist online magazine run by Jared Taylor; Brad Griffin, who blogs under the name Hunter Wallace on the website Occidental Dissent; and Michael Hill of the Traditionalist Workers Party were also suspended.

White nationalist Richard Spencer, whose account was not suspended, tweeted that he had lost more than a hundred followers in the past 24 hours and noted that he didn’t “see any systematic method to the #TwitterPurge.”

Spencer tweet

There appeared to be some inconsistencies in the enforcement. Still on Twitter was David Duke, with some of his posts hidden behind the “sensitive material” warning. However, Twitter allowed him to keep the message “It’s Ok To Be White” as his header, even though the same phrase was hidden by the warning on his pinned tweet.

When contacted, Twitter said via email to CNBC that it doesn’t comment on individual accounts for privacy and security reasons.

However, the company added that 30 days ago it made users aware that new policies on abusive behavior would come into effect on December 18.

–The Associated Press contributed to this report.