Jonestown Massacre

We're talking about one of the largest mass killings or rather mass murder-suicides in US history.

References:

Jim Jones | American Experience | Official Site | PBS

Jim Jones | Biography, Jonestown, Massacre, Peoples Temple, & Facts | Britannica

Jim Jones - Son, Movies & Documentaries (biography.com)

Jonestown Massacre: What You Should Know About Cult Murder-Suicide – Rolling Stone