D (PROSE: The Stranger)

'The Daleks have worked out where the munitions factories are. They're tunnelling through the planet to find them.'

[...]

There was a terrible shriek of tearing metal as the floors and walls of the factory had begun to shred. Something was drilling through them—more than one something. Like giant screws, these somethings were twisting holes in the walls and floors as they smashed their way inside.
The children ran in frightened circles, and Senior Tahl tried to gather them up.
A second or two later, the giant screw-things had withdrawn and Daleks flew in through the holes.