2 Kings 6:18-20:

And when they came down to him, Elisha prayed unto the LORD, and said, Smite this people, I pray thee, with blindness.  And he smote them with blindness according to the word of Elisha.
And Elisha said unto them, This is not the way, neither is this the city: follow me, and I will bring you to the man whom ye seek.  But he led them to Samaria.
And it came to pass, when they were come into Samaria, that Elisha said, LORD, open the eyes of these men, that they may see.  And the LORD opened their eyes, and they saw; and behold, they were in the midst of Samaria.

Notes on 2 Kings 6:18-20:

One interesting thing you can see here is that this incident included a mass healing of blind people!  If God could do a mass healing of blind people back then, He can certainly do a mass healing of blind people today!  I knew a minister who had blind people healed by the dozens in single services in Africa, so it’s happened in modern times.

See also:

Objection: God Creates Dumb, Deaf and Blind People (Exodus 4:11)
Condition: Blindness