I saw a similar kind of incident first hand - it was no explosion - but a good demonstration of pressure getting out of hand.
A CNG service shop had inverted a cars cylinder to empty the oil contents from it, the service man opened the tapered brass fitting from the cylinder - like - he was sitting on it and the cylinder valve was facing inside the shop the back facing the other wall.
when all pressure had been relieved the valve was unscrewed the cylinder shot from the person hitting the wall breaking through it, hitting a dump and a stranded old heap car - it also completely unrooted the dump walls, the persons clothes were blown to smithereens - due to the shock wave of sound.
If such a small amount of pressure can break through concrete walls - it can do anything