Revelation 9:16-18

16The number of mounted troops was twice ten thousand times ten thousand; I heard their number.

17And this is how I saw the horses in my vision and those who rode them: they wore breastplates the color of fire and of sapphire and of sulfur, and the heads of the horses were like lions' heads, and fire and smoke and sulfur came out of their mouths.

18By these three plagues a third of mankind was killed, by the fire and smoke and sulfur coming out of their mouths.