Tipsters alerted the FBI to a threatening post on the anonymous message board 8chan minutes before a gunman opened fire at a California synagogue, an FBI official said https://t.co/2KECADyzvj https://t.co/XoWTYon7nv

Tipsters alerted the FBI to a threatening post on the anonymous message board 8chan minutes before a gunman opened fire at a California synagogue, an FBI official said https://t.co/2KECADyzvj https://t.co/XoWTYon7nv (via Twitter http://twitter.com/CNN/status/1122968835391410182)