Stocks pulled back from the record highs they've been setting as bond yields continued to fall and investors turned cautious.
The S&P 500 fell 0.9%. Technology, financial and industrial companies had some of the biggest losses.
The yield on the 10-year Treasury note fell to 1.30% from 1.32% a day earlier.
The benchmark yield, which is used to set rates on mortgages and many other kinds of loans, has been falling steadily in recent weeks as traders shift money into bonds.
The 10-year yield traded as high as 1.74% at the end of March.