From the Book of Mormon:

Ether 8:

22 And whatsoever nation shall uphold such secret combinations, to get power and gain, until they shall spread over the nation, behold, they shall be destroyed; for the Lord will not suffer that the blood of his saints, which shall be shed by them, shall always cry unto him from the ground for vengeance upon them and yet he avenge them not.

23 Wherefore, O ye Gentiles, it is wisdom in God that these things should be shown unto you, that thereby ye may repent of your sins, and suffer not that these murderous combinations shall get above you, which are built up to get power and gain--and the work, yea, even the work of destruction come upon you, yea, even the sword of the justice of the Eternal God shall fall upon you, to your overthrow and destruction if ye shall suffer these things to be.

24 Wherefore, the Lord commandeth you, when ye shall see these things come among you that ye shall awake to a sense of your awful situation, because of this secret combination which shall be among you; or wo be unto it, because of the blood of them who have been slain; for they cry from the dust for vengeance upon it, and also upon those who built it up.

25 For it cometh to pass that whoso buildeth it up seeketh to overthrow the freedom of all lands, nations, and countries; and it bringeth to pass the destruction of all people, for it is built up by the devil, who is the father of all lies; even that same liar who beguiled our first parents, yea, even that same liar who hath caused man to commit murder from the beginning; who hath hardened the hearts of men that they have murdered the prophets, and stoned them, and cast them out from the beginning.

26 Wherefore, I, Moroni, am commanded to write these things that evil may be done away, and that the time may come that Satan may have no power upon the hearts of the children of men, but that they may be persuaded to do good continually, that they may come unto the fountain of all righteousness and be saved.