Jude 5-7 & 2 Pet 2:4-7
Jude 1:5 (NIV) Though you already know all this, I want to remind you that the Lord delivered his people out of Egypt, but later destroyed those who did not believe.
6 And the angels who did not keep their positions of authority but abandoned their own home--these he has kept in darkness, bound with everlasting chains for judgment on the great Day.
7 In a similar way, Sodom and Gomorrah and the surrounding towns gave themselves up to sexual immorality and perversion. They serve as an example of those who suffer the punishment of eternal fire.
2Pet 2:4 (NIV) For if God did not spare angels when they sinned, but sent them to hell, putting them into gloomy dungeons to be held for judgment;
5 if he did not spare the ancient world when he brought the flood on its ungodly people, but protected Noah, a preacher of righteousness, and seven others;
6 if he condemned the cities of Sodom and Gomorrah by burning them to ashes, and made them an example of what is going to happen to the ungodly;
7 and if he rescued Lot, a righteous man, who was distressed by the filthy lives of lawless men