S&P 500 sinks below 700 in Wall St rout
* Another government bailout of American International Group and the insurer's record $61.7 billion quarterly loss raised fears that efforts to stem the financial crisis still are not enough.
* The Dow Jones industrial average was down 291.59 points, or 4.13 percent, at 6,771.34.
The Standard & Poor's 500 Index was down 33.09 points, or 4.50 percent, at 702.00.
In the last half hour of regular trading, the S&P 500 hit an intraday low of 699.70 -- its lowest since October 1996.
* The Nasdaq Composite Index was down 52.54 points, or 3.81 percent, at 1,325.30.
(Reporting by Ellis Mnyandu; Editing by Jan Paschal)