SpaceX had a very sudden and upsetting anomaly just before the static test fire of their Falcon 9 rocket on September 1, 2016.
I’m a huge fan of SpaceX and their relentless innovation toward the final frontier. I wish them best of luck in their return to flight. For more information on what happened, check out this excellent FAQ written by the moderators of the subreddit r/spacex. Direct link to the full video above is here.