Video
It appears the B18.3 test tank buckled below the common dome level during crush testing at the Masseys test site this evening. It's currently unclear whether this was intentional or not. Watch till the end for a zoomed in view.
The B18.3 test article seems to have suffered a structural failure during qualification testing of the Integrated Hot Staging Ring for the V3 Booster.
It appears that it buckled beneath the common dome weld which is not ideal, considering that was not the component being tested for structural integrity.
Hopefully they were able to gather the data they were hoping for and won't need to replace this test article in order to complete this extremely important test.