Investors clamored into the safety of U.S. government bonds, sending the 30-year Treasury bond yield below 2% for the first time ever and the 10-year Treasury note yield below 1.5%, a three-year low.

Around 2:00 p.m. ET, the yield on the benchmark 10-year Treasury note, which moves inversely to price, hit a three-year low of 1.475%, while the yield on the 30-year Treasury bond was at 1.944%, after earlier falling to 1.941% for the first time ever. The 2-year Treasury yield was 1.467%, its lowest level since Oct. 2017.