Jude 1:5-7

5Now I want to remind you, although you came to know all these things once and for all, that Jesus saved a people out of Egypt and later destroyed those who did not believe;

6and the angels who did not keep their own position but abandoned their proper dwelling, he has kept in eternal chains in deep darkness for the judgment on the great day.

7Likewise, Sodom and Gomorrah and the surrounding towns committed sexual immorality and perversions, and serve as an example by undergoing the punishment of eternal fire.