Originally all angels were created good. The Scriptures speak of
a fall of angels--"the angels that sinned."
2 Pet. 2:4--"For if God spared not the angels that sinned, but cast
them down to hell, and delivered them into chains of darkness, to
be reserved unto judgment." Jude 6--"And the angels which kept not
their first estate, but left their own habitation, he hath reserved
in everlasting chains under darkness unto the judgment of the great
day."