SAN FRANCISCO (Reuters) – Facebook Inc said Tuesday it has suspended accounts associated with white nationalist groups after some advocated bringing weapons to the current wave of anti-racist protests.

Company officials also said they removed accounts falsely claiming allegiance to antifa in order to bring discredit to the anti-fascist movement.

Antifa adherents have said they focus on defending people from attacks by authorities or vigilantes, but they have been vilified by President Donald Trump who, without citing evidence, said they were instigators of anti-police violence.

Some of the removed white nationalist accounts were associated with the Proud Boys, which Facebook previously classified as a dangerous group. The others had connections to a group called the American Guard, which is now classified the same way.

Multiple Facebook executives described the action on condition they not be identified. They said they acted based on behavior, not the politics of any content, and that Facebook had not designated antifa as dangerous.

The company said it was looking closer at accounts discussing protests when it saw what it deemed white nationalist accounts encouraging violence.

The misleading antifa accounts were removed for “inauthentic behavior,” because they purported to be something they were not, Facebook said.

As with a false antifa tweet that Twitter Inc tied to a third white nationalist group and which was widely distributed as a screen shot, the Facebook executives said Tuesday the goal of such content is often not to win thousands of followers but to plant a single false flag that can be used to sow distrust about the target group.

Facebook declined to comment on whether it had been in touch with law enforcement, which it typically does in cases of an imminent threat.