Facebook took down advertisements for President Donald Trump‘s reelection campaign on Thursday, saying they violated company policy by including a large red triangle that was used by Nazis to classify political prisoners of war.

“Dangerous MOBS of far-left groups are running through our streets and causing absolute mayhem,” the ads read. Below the ad was the red triangle, seemingly referring to Antifa, a loosely organized group of anti-fascists upon Trump has scapegoated for the damage and vandalism occurring alongside some George Floyd protests.

“We removed these posts and ads for violating our policy against organized hate,” Facebook said in a statement. “Our policy prohibits using a banned hate group’s symbol to identify political prisoners without the context that condemns or discusses the symbol.”

The Trump campaign’s communications director, Tim Murtaugh, told the New York Times that the red triangle is commonly associated with Antifa.

“The red triangle is a common Antifa symbol used in an ad about Antifa. Pretty straightforward,” he said, noting that a similar red triangle was a standard emoji.

He also pointed out that the red triangle in not listed in the Anti-Defamation League’s database of hate symbols.

However, the Anti-Defamation League condemned the Trump campaign for using the symbol, underscoring that their database does not track all Nazi-era symbols, rather only those used by modern-day white supremacists.

“Whether aware of the history or meaning, for the Trump campaign to use a symbol — one which is practically identical to that used by the Nazi regime to classify political prisoners in concentration camps — to attack his opponents is offensive and deeply troubling,” Jonathan Greenblatt, the chief executive of the Anti-Defamation League told the Times. “It is not difficult for one to criticize their political opponent without using Nazi-era imagery. We implore the Trump campaign to take greater caution and familiarize themselves with the historical context before doing so.”