U.S. Treasury yields fell on Wednesday, as investors monitored tensions between the U.S. and North Korea.

The yield on the benchmark 10-year Treasury note hit a six-week low before trading at 2.246 percent at 1:44 p.m. ET, while the yield on the 30-year Treasury bond was lower at 2.824 percent. Bond yields move inversely to prices.

The 5-year Treasury note also hit a low Wednesday, falling to 1.768, its lowest level since June 27.

On Tuesday, U.S. President Donald Trump warned the Asian country about facing "fire and fury" if North Korea delivers more threats against the U.S.

Shortly after this announcement, North Korea said it was "carefully examining" the idea of a missile strike on Guam, a U.S. Pacific territory; Reuters reported citing the North's state-run KCNA.

"I think this boils down to China's reaction," Peter Tchir, Brean Capital, head of macro strategy, said in an email to CNBC. "If we do something with North Korea that causes relationship with China to deteriorate, its bad for markets. Anything else seems likely to be short lived in terms of causing market problems."

Other sovereign bond yields also fell, including on the 10-year German bund.