The full story from Chicken Noodle News is
here. This piece does not mention whether the pilot was in fact the flightleader. It does introduce speculation from an "off-duty air traffic controller" that a bird strike might have been the cause (he said it, I didn't!).
Certainly a tragedy, even more so when the "elite" are involved. It's my understanding airshow rules are pretty stringent in the US, but nevertheless this might invite even more scrutiny (parts of the wreckage reportedly landed in a residential area).