2 Peter 2:4

For if God did not spare the angels when they sinned, but cast them deep into hell, placing them in chains of darkness to be held for judgment;

Note Greek cast them into Tartarus; see the First Book of Enoch (1 Enoch 13:1–11 and 1 Enoch 20:1–4).

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;

For if God didn’t spare angels when they sinned, but cast them down to Tartarus, and committed them to pits of darkness to be reserved for judgment;

Note Tartarus is another name for Hell

For if God spared not angels when they sinned, but cast them down to hell, and committed them to pits of darkness, to be reserved unto judgment;