Revelation 20:13-15

13And the sea gave up the dead who were in it, and death and Hades (the realm of the dead) surrendered the dead who were in them; and they were judged and sentenced, every one according to their deeds.

14Then death and Hades [the realm of the dead] were thrown into the lake of fire. This is the second death, the lake of fire [the eternal separation from God].

15And if anyone’s name was not found written in the Book of Life, he was hurled into the lake of fire.