Revelation 9:13-16

13Then the sixth angel blew his trumpet, and I heard a voice from the four horns of the golden altar before God,

14saying to the sixth angel who had the trumpet, "Release the four angels who are bound at the great river Euphrates."

15So the four angels, who had been prepared for the hour, the day, the month, and the year, were released to kill a third of mankind.

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