4 Bible Verses about Fallen Angels

"I saw Satan fall like a lightning-flash out of Heaven," He replied.

And war broke out in Heaven, Michael and his angels engaging in battle with the Dragon. The Dragon fought and so did his angels; but they were defeated, and there was no longer any room found for them in Heaven. The great Dragon, the ancient serpent, he who is called 'the Devil' and 'the Adversary' and leads the whole earth astray, was hurled down: he was hurled down to the earth, and his angels were hurled down with him.read more.
Then I heard a loud voice speaking in Heaven. It said, "The salvation and the power and the Kingdom of our God have now come, and the sovereignty of His Christ; for the accuser of our brethren has been hurled down--he who, day after day and night after night, was wont to accuse them in the presence of God. But they have gained the victory over him because of the blood of the Lamb and of the testimony which they have borne, and because they held their lives cheap and did not shrink even from death. For this reason be glad, O Heaven, and you who live in Heaven! Alas for the earth and the sea! For the Devil has come down to you; full of fierce anger, because he knows that his appointed time is short." And when the Dragon saw that he was hurled down to the earth, he went in pursuit of the woman who had given birth to the male child. Then, the two wings of a great eagle were given to the woman to enable her to fly away into the Desert to the place assigned her, there to be cared for, for a period of time, two periods of time, and half a period of time, beyond the reach of the serpent. And the serpent poured water from his mouth--a very river it seemed--after the woman, in the hope that she would be carried away by its flood. But the earth came to the woman's help: it opened its mouth and drank up the river which the Dragon had poured from his mouth. This made the Dragon furiously angry with the woman, and he went elsewhere to make war upon her other children--those who keep God's commandments and hold fast to the testimony of Jesus.

For God did not spare angels when they had sinned, but hurling them down to Tartarus consigned them to caves of darkness, keeping them in readiness for judgement.