"I'm getting the sense it's very emotional trading," said Cresset Capital's Jack Ablin. "So investors are on high alert for any news that could be disappointing or just anything particularly related to the banks."

Major indices spent most of the day deep in the red, but the Nasdaq popped into positive territory at the end of the day after the Swiss National Bank said Credit Suisse had adequate capital, but that it was ready to make liquidity available to the institution if needed.

The statement came after the shares of the giant bank closed down nearly 25 percent on the Swiss exchange.

The Dow Jones Industrial Average ended at 31,874.57, down 0.9 percent, but nearly 450 points above its session low.

The broad-based S&P 500 declined 0.7 percent to 3,891.93, while the tech-rich Nasdaq Composite Index added 0.1 percent at 11,434.05.

Worries about Credit Suisse afflicted US banks of all sizes, with giants like JPMorgan Chase and Citigroup losing around five percent and the embattled midsized lender First Republic Bank slumping 21.4 percent.

Anxiety about the banks overshadowed US economic data that suggested a slowing economy that could ease pressure on the Federal Reserve next week.

US wholesale prices fell unexpectedly last month, while retail sales also contracted, driven by declines in sales at department and furniture stores.

The data has contributed to the investor view that the Fed could pause its interest rate increases next week.

Among other stocks, petroleum-linked shares fell sharply as US oil prices finished at their lowest level since December 2021 amid recession worries.

Chevron dropped 4.3 percent and Halliburton and Transocean both slumped around 9.0 percent.