Bank shares tumble amid global plunge
Among the losers, shares of Citigroup tumbled 9 percent to $11.95 before the bell, while those of Goldman Sachs slid more than 8 percent to $99.48.
The Financial Select Sector SPDR , an exchange-traded fund which tracks the performance of stocks in the Standard & Poor's 500 financials group, slid 6.1 percent to $13.60.
(Reporting by Ellis Mnyandu, editing by Walker Simon)