As Facebook and YouTube work to take down videos of Friday’s terrorist killings that left 50 dead in New Zealand, white supremacists are finding new ways to keep the content alive.

Video attributed to the alleged shooter, 28-year-old Brenton Tarrant, broadcast the Christchurch mosque attack live on Facebook, with images of men, women and children being gunned down. The video spread quickly via popular sites like YouTube—and then kept popping up in other parts of the internet even as mainstream sites tried to delete it.

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