“11 And after three days and an half the Spirit of life from God entered into them, and they stood upon their feet; and great fear fell upon them which saw them.
12 And they heard a great voice from heaven saying unto them, Come up hither. And they ascended up to heaven in a cloud; and their enemies beheld them.”
(Rev 11:11-12 KJV)
After lying dead in the streets for three and a half days, God will resurrect the two witnesses. This resurrection is witnessed by their enemies, who will have great fear because they will realize that God is more powerful and they cannot beat God. The two witnesses are then caught up to heaven as their enemies watch. The phrase “come up hither” is a calling to heaven just like the Church is called and caught up in the clouds.
“16 For the Lord himself shall descend from heaven with a shout, with the voice of the archangel, and with the trump of God: and the dead in Christ shall rise first:
17 Then we which are alive and remain shall be caught up together with them in the clouds, to meet the Lord in the air: and so shall we ever be with the Lord.”
(1Th 4:16-17 KJV)