[HoustonCurmudgeon]

"John McCarthy who works for an American company, Berco Services of Houston, Texas, which specialises in horizontal drilling, said: “If you know where the entrance to the caves is, you could drill a hole 20in in diameter through solid rock for up to two miles at the rate of 1,000ft a day."

To do this you will need drilling mud. When you hit the caves just keep pumping. A few days and the whole damn thing is filled up.

[TomGuy]

Squirt in a few thousand gallons of that expanding insulating foam...

Would be a Pulitzer to capture the expressions on Al-quadas' faces!

[Dog Gone]

To do this you will need drilling mud.

I doubt this is the way they are going to do it unless they are very sure that they have located the precise cave and that a frontal assault would be too difficult.

But if they decide to drill, it wouldn't be necessary to use drilling mud. Air drilling would work fine for a few thousand feet of rock.

It's very loud, though, and there would be no element of surprise. More than likely, the noise would cause the inhabitants to make a run for it long before the cave was penetrated.