According to the BBC the shooter himself posted and live steamed on Facebook [0]. "Someone", possibly the shooter or possibly someone watching him on Facebook, crossposted it to 8ch. I think a lot of times the alt websites get hate for stuff that's clearly happening on the mainstream websites as well. I'd estimate that the alt websites have much higher concentrations of hate, but probably less overall hate than the mainstream websites.

0 - https://web.archive.org/web/20190317214903/https://www.bbc.c...