Revelation 6:8-10 New International Version - UK (NIVUK)
8 I looked, and there before me was a pale horse! Its rider was named Death, and Hades was following close behind him. They were given power over a quarter of the earth to kill by sword, famine and plague, and by the wild beasts of the earth.
9 When he opened the fifth seal, I saw under the altar the souls of those who had been slain because of the word of God and the testimony they had maintained. 10 They called out in a loud voice, ‘How long, Sovereign Lord, holy and true, until you judge the inhabitants of the earth and avenge our blood?’