A funny thing happened at 1101ET. Amid the deep plunge in stocks, 'someone' suddenly traded an enormous block of e-mini S&P futures which appeared to stall the sell-off (for now). This followed a similar (but smaller) block trade at 1042ET which also extracted all the liquidity from the market momentarily and enabled a brief rally.
That is twice we have seen a big block followed by a rally in futures...
and a close up shows the shocking ripple as liquidity was sucked away by the huge block trade...
Via @NanexLLC