Actually all you have to do to know how most of the population will die is go to the King James Bible as it says in the book of Revelation:
And the fifth angel sounded, and I saw a star fall from heaven unto the earth: and to him was given the key of the bottomless pit.
And he opened the bottomless pit; and there arose a smoke out of the pit, as the smoke of a great furnace; and the sun and the air were darkened by reason of the smoke of the pit.
And there came out of the smoke locusts upon the earth: and unto them was given power, as the scorpions of the earth have power.
And it was commanded them that they should not hurt the grass of the earth, neither any green thing, neither any tree; but only those men which have not the seal of God in their foreheads.
And to them it was given that they should not kill them, but that they should be tormented five months: and their torment [was] as the torment of a scorpion, when he striketh a man.
And in those days shall men seek death, and shall not find it; and shall desire to die, and death shall flee from them.
And the shapes of the locusts [were] like unto horses prepared unto battle; and on their heads [were] as it were crowns like gold, and their faces [were] as the faces of men.
And they had hair as the hair of women, and their teeth were as [the teeth] of lions.
And they had breastplates, as it were breastplates of iron; and the sound of their wings [was] as the sound of chariots of many horses running to battle.
And they had tails like unto scorpions, and there were stings in their tails: and their power [was] to hurt men five months.
And they had a king over them, [which is] the angel of the bottomless pit, whose name in the Hebrew tongue [is] Abaddon, but in the Greek tongue hath [his] name Apollyon.
One woe is past; [and], behold, there come two woes more hereafter.
And the sixth angel sounded, and I heard a voice from the four horns of the golden altar which is before God,
Saying to the sixth angel which had the trumpet, Loose the four angels which are bound in the great river Euphrates.
And the four angels were loosed, which were prepared for an hour, and a day, and a month, and a year, for to slay the third part of men.
And the number of the army of the horsemen [were] two hundred thousand thousand: and I heard the number of them.
And thus I saw the horses in the vision, and them that sat on them, having breastplates of fire, and of jacinth, and brimstone: and the heads of the horses [were] as the heads of lions; and out of their mouths issued fire and smoke and brimstone.
By these three was the third part of men killed, by the fire, and by the smoke, and by the brimstone, which issued out of their mouths.
For their power is in their mouth, and in their tails: for their tails [were] like unto serpents, and had heads, and with them they do hurt.
And the rest of the men which were not killed by these plagues yet repented not of the works of their hands, that they should not worship devils, and idols of gold, and silver, and brass, and stone, and of wood: which neither can see, nor hear, nor walk:
Neither repented they of their murders, nor of their sorceries, nor of their fornication, nor of their thefts.
Revelation 9:1-21 (KJV)
And when he had opened the seventh seal, there was silence in heaven about the space of half an hour.
And I saw the seven angels which stood before God; and to them were given seven trumpets.
And another angel came and stood at the altar, having a golden censer; and there was given unto him much incense, that he should offer [it] with the prayers of all saints upon the golden altar which was before the throne.
And the smoke of the incense, [which came] with the prayers of the saints, ascended up before God out of the angel's hand.
And the angel took the censer, and filled it with fire of the altar, and cast [it] into the earth: and there were voices, and thunderings, and lightnings, and an earthquake.
And the seven angels which had the seven trumpets prepared themselves to sound.
The first angel sounded, and there followed hail and fire mingled with blood, and they were cast upon the earth: and the third part of trees was burnt up, and all green grass was burnt up.
And the second angel sounded, and as it were a great mountain burning with fire was cast into the sea: and the third part of the sea became blood;
And the third part of the creatures which were in the sea, and had life, died; and the third part of the ships were destroyed.
And the third angel sounded, and there fell a great star from heaven, burning as it were a lamp, and it fell upon the third part of the rivers, and upon the fountains of waters;
And the name of the star is called Wormwood: and the third part of the waters became wormwood; and many men died of the waters, because they were made bitter.
And the fourth angel sounded, and the third part of the sun was smitten, and the third part of the moon, and the third part of the stars; so as the third part of them was darkened, and the day shone not for a third part of it, and the night likewise.
And I beheld, and heard an angel flying through the midst of heaven, saying with a loud voice, Woe, woe, woe, to the inhabiters of the earth by reason of the other voices of the trumpet of the three angels, which are yet to sound!
Revelation 8:1-13 (KJV)
And there went out another horse [that was] red: and [power] was given to him that sat thereon to take peace from the earth, and that they should kill one another: and there was given unto him a great sword.
And when he had opened the fourth seal, I heard the voice of the fourth beast say, Come and see.
And I looked, and behold a pale horse: and his name that sat on him was Death, and Hell followed with him. And power was given unto them over the fourth part of the earth, to kill with sword, and with hunger, and with death, and with the beasts of the earth.
Revelation 6:4, 7-8
There are also scriptures in the book of Ezekiel talking about the coming War with Gog and Magog [Russia] not to mention a bunch of other nations coming with him including: Libya, Turkey, Persia [Iran] among others. They will invade Israel, and they will be destroyed by God [Jesus Christ].
This will be many deaths though as well, and it will be God's Judgments that kill many people on this earth according to Revelation and his Word. It's possible God will use these people or "elites" to do it, but it will still be his judgments one way or another.
Even the more reason to get saved as soon as possible, because Americas day will come when its judged soon - Probably within the next few years at least.