Treasurys extended their downward slide Thursday after the government's auction of 30-year bonds saw tepid investor demand.
The Treasury Department auctioned $13 billion of 30-year bonds at a high yield of 3.084 percent, versus 3.138 percent in June. The bid-to-cover ratio, an indicator of demand, was 2.23, lower than the 2.38 recent average.
Yields, which move inversely to prices, hit session highs after the announcement. The yield on the benchmark 10-year Treasury note increased 9 basis points to 2.289 percent, while the 30-year bond yield rose more than 10 basis points to 3.081 percent.
Indirect bidders, which include major central banks, were awarded 51.1 percent, more than the 49 percent average. Direct bidders, which includes domestic money managers, bought 8 percent, versus a recent average of 15 percent.
"Following a decent three-year note auction on Tuesday and a good 10-year yesterday, today's 30-year bond auction was weak," Peter Boockvar, chief market analyst at the Lindsey Group, said in a note.
"Yields on the longer end of the curve remain well above the late January lows and I don't believe that is because the global growth outlook is any better."