Facebook is updating its hate speech policy.

Just two years ago, founder and chief executive Mark Zuckerberg told Recode that while he found Holocaust deniers “deeply offensive”, it was “hard to impugn intent and to understand the intent.”

On Monday, however, Zuckerberg walked back on his previous comments, announcing via Facebook that the social media site will ban Holocaust denial hate speech and direct users to “authoritative sources to get accurate information.”

Reflecting on this change Zuckerberg writes that he “has struggled with the tension between standing for free expression and the harm caused by minimizing or denying the horror of the Holocaust. My own thinking has evolved as I’ve seen data showing an increase in anti-Semitic violence, as have our wider policies on hate speech.”

Earlier this year Facebook banned hate speech involving harmful stereotypes and accounts related to militia groups and QAnon, a conspiracy theory movement. However, Zuckerberg has come under increased pressure to act more aggressively towards hate speech and disinformation.

A July campaign coordinated by the New York-based Conference on Jewish Material Claims Against Germany––a nonprofit organization that secures compensation for Holocaust survivors––featured Holocaust survivors urging Facebook to remove denial posts, the Associated Press reports. The campaign used the Facebook platform itself to post one video per day using the hashtag #NoDenyingIt.

The reversal also comes after a nationwide survey commissioned by the CJMCAG found a disturbing lack of Holocaust knowledge among millennials and Gen Zers. A startling 49 percent reported to have “seen Holocaust denial or distortion posts on social media or elsewhere online,” the survey noted.

This past February, the Anti-Defamation League also reported that white supremacist propaganda distributed around U.S. college campuses was at an all-time high—2,713 cases were reported compared to 1,214 in 2018, a nearly 160 percent increase.

While the new policy will take “some time” to implement cautions Monika Bickert, head of content policy at Facebook, the move marks a significant shift in the social media’s efforts to curb ignorance and hate.

The Claims Conference put it succinctly, tweeting out, “Survivors spoke! Facebook listened.”