>https://en.wikipedia.org/wiki/Balvano_train_disaster The now-forgotten Balvasno tragedy remains Italy's worst rail disaster; forgotten mostly because Italy was under Fascist rule at the time.
Unlike most rail disasters, it never involved a crash or collision. Instead, a goods train doubleheaded by coal burning steam locomotives stalled in a long tunnel, which then proceeded to fill with toxic smoke that asphyxiated not only the crew of the train but the hundreds of illegal stowaway vagrants onboard. They were overcome by carbon monoxide poisoning before any of them could realize what was happening.
