Indeed it was widely believed that they tried a number of times to ignite fires that would destroy the world and hasten the coming of their new kingdom.
Christians were also accused of cannibalism and incest.
In response to Pliny's requests for guidance the Emperor Trajan advised moderation. Anonymous accusers should be ignored, and accusations made by responsible citizens should be properly investigated.
Christians were sporadically investigated by the authorities, mainly because they were believed to have been promoting sedition.
As far as we know, no one in the classical world hit upon the idea of exterminating others because of the god they chose to worship.
As Gibbon put it, quoting Seneca the Younger: "The various modes of worship which prevailed in the Roman world, were all considered by the people as equally true, by the philosopher as equally false, and by the magistrate as equally useful.
For their part, the Roman oppressors were brutal and merciless, and killed the unfortunate Christians for no better reason than that they chose a new and harmless faith.
Yet even these heartless pagans could not help but be impressed by the fortitude of their victims.
Gibbon noted of Jewish beliefs that "according to the maxims of universal toleration, the Romans protected a superstition which they despised".
Some declined to answer any questions at all even refusing to give their names or nationalities.
Sometimes they lied, for example claiming to be Old Testament characters like Elijah or Daniel. No doubt the accusations of cannibalism were mistaken, but Christians were certainly guilty of other crimes.
Tacitus wrote around AD 110 that they were "notoriously depraved".
Nero, he noted, had arrested Christians in Rome for arson and for other antisocial behaviour.