All Power Display glass shatter

I had been startled into a saluting awareness in the early hours of the morning when the sound of glass shattering from my living room had caused me to react in a fight or flight situation. I investigated the source of the noise and anxiously rushed into the room hoping not to encounter some break in progress luckily no window had been broken into but the source of the sound had an aftermath and it did not come from outside but inside the house. It turns out to be the large plane glass that use to be clear as glass now cobbled with a spider web of glass fractures. I have no idea as to the cause of such a catastrophic glass collapse. I hope that someone could fill me into the mystery that has baffled me as to the cause because 4 other display cases of the same make/model.

Post time: 09-23-2017