Verse 9

وَجَعَلْنَا مِنۢ بَيْنِ أَيْدِيهِمْ سَدًّا وَمِنْ خَلْفِهِمْ سَدًّا فَأَغْشَيْنَـٰهُمْ فَهُمْ لَا يُبْصِرُونَ

And We place a barrier in front of them and a barrier behind them, We then completely cover them and they will not be able to see.