Until just recently, Facebook allowed advertisers to target messages to people interested in Anti-Semitic topics, such as “Jew haters” and “how to burn Jews.”

The social-media giant only ended the practice this week after journalists inquired about it.

In a new report, nonprofit outlet ProPublica said it found the topics in Facebook’s self-service ad-buying platform, and paid $30 to test them with its own content. Other categories it found were “why Jews ruin the world” and “Hitler did nothing wrong.”

The anti-Semitic categories were created by an algorithm rather than by people, ProPublica reported. Some 2,300 people had expressed interest in them.

Facebook, the world’s largest social network, said in a statement that it had removed the ability to buy targeted marketing based on those topics and believed the use of the topics in ad campaigns had not been widespread.

Along with Google, Facebook dominates the fast-growing market for online advertising, in part because it lets marketers target their ads based on huge volumes of data.

This news comes just a week after Facebook admitted it had sold $100,000 worth of ads to inauthentic accounts likely linked to Russia during the election. Russia has been accused of using Facebook and other platforms to spread fake news in an attempt to influence the 2016 presidential elections.