Revelation 6:8-10

Young's Literal Translation

⁸ and I saw, and lo, a pale horse, and he who is sitting upon him -- his name is Death, and Hades doth follow with him, and there was given to them authority to kill, (over the fourth part of the land,) with sword, and with hunger, and with death, and by the beasts of the land.

⁹ And when he opened the fifth seal, I saw under the altar the souls of those slain because of the word of God, and because of the testimony that they held,

¹⁰ and they were crying with a great voice, saying, `Till when, O Master, the Holy and the True, dost Thou not judge and take vengeance of our blood from those dwelling upon the land?'