Sometimes, people’s best intentions go terribly wrong. That was the case this week when Facebook users started sharing a child pornography video in a misguided effort to catch the perpetrator, according to officials. The video spread widely with an accompanying message urging people to pass it along and identify the man responsible. Facebook finally caught on to what was happening and stopped it on Monday — but not before the disturbing video was blindly shared and seen by thousands.

“We are aware of this issue,” a Facebook spokesperson told BuzzFeed News. “We reported the video to the appropriate authorities, and we have used PhotoDNA technology to automatically prevent future uploads and shares. Sharing any kind of child exploitative imagery using Facebook or Messenger is not acceptable — even to express outrage.”

Local police departments across the country have issued warnings about the video, urging citizens not to share it. One authority even called it a “nationwide epidemic.” Thankfully, the video will be blocked moving forward, but that can’t undo the thousands of views it has already received.

This whole sad case just illustrates how much power Facebook wields, even without meaning to. The perpetrator was ultimately captured, but the video of his crimes never should’ve gone viral in the first place.