The Fed cut interest rates to just 1%.

The markets' reaction was mixed. Stocks plunged more than 360 points in the final minutes of trading, losing the momentum gained after the Federal Reserve's decision to cut a key interest rate to help alleviate fears of further economic deterioration.

The Dow Jones industrial average closed down 0.8 percent, with a loss of more than 74 points. The broader Standard & Poor's 500 fell 1.1 percent, or 10 points. The tech-heavy Nasdaq closed up nearly 8 points, a gain of about half a percent.