The Divine Institutes

A fit and auspicious day was sought out for the accomplishment of this undertaking; and the festival of the god Terminus, celebrated on the sevens of the kalends of March, was chosen, in preference to all others, to terminate, as it were, the Christian religion.

…of woes which befell not only the Christians, but the whole earth. When that day dawned, in the eighth consulship of Diocletian and seventh of Maximian, suddenly, while it was yet hardly light, the prefect, together with chief commanders, tribunes, and officers of the treasury, came to the church in Nicomedia, and the gates having been forced open, they searched everywhere for an image of the Divinity. The books of the Holy Scriptures were found, and they were committed to the flames; the utensils and furniture of the church were abandoned to pillage: all was rapine, confusion, tumult. That church, situated on rising ground, was within view of the palace; and Diocletian and Galerius stood, as if on a watch-tower, disputing long whether it ought to be set on fire. The sentiment of Diocletian prevailed, who dreaded lest, so great a fire being once kindled, some part of the city might he burnt; for there were many and large buildings that surrounded the church. Then the Pretorian Guards came in battle array, with axes and other iron instruments, and having been let loose everywhere, they in a few hours levelled that very lofty edifice with the ground.