> I never heard from anyone.
What is the FBI doing if they're not working on cases like this or domestic terrorism/mass shootings? We continue to have both classes of crimes in droves.
In all seriousness, this is probably an international crime and they just do not have the resources to chase them all down.
Most mass shootings don't have a lot of the FBI to investigate. The perpetrator often dies on site, so they can't be charged with anything. FBI will likely investigate if there were any co-conspirators, and may work with ATF to determine how the perpetrator obtained the firearm(s). Many times we hear that the perpetrator was "on the FBI's radar", but most of the time, there was no unlawful conduct before the shooting, so what are they supposed to do?