The upheaval in stocks has been grabbing all the headlines, but there is a bigger problem looming in another corner of the financial markets that rarely gets headlines: Investors are dumping U.S. government bonds.

Normally, investors rush into Treasurys at a whiff of economic chaos but now they are selling them as not even the lure of higher interest payments on the bonds is getting them to buy.

The freak development has experts worried that big banks, funds and traders are losing faith in America as a good place to store their money.