I wonder if all three Cardinals (who opposed Francis) who have died in the last two months were all residents of Italy. Surely it would be easier to do them in if they were close by like that.
I hope that's not the case, but heretics have been known to be violent. The Arians spring to mind, in this regard. They could be quite violent. Pope Liberius was kidnapped by the Arians and held in exile by them for two years, until he finally agreed to exile St. Athanasius (it is thought that Pope Liberius
was threatened with death if he did not agree to do so).
The modernists may not seem to be violent, for the most part, but they are sly. I wouldn't put it past them.