Treasurys extended earlier gains on Wednesday after the government's auction of 10-year notes, the secondset of this week's $67 billion in U.S. debt supply.
The Treasury Department auctioned $24 billion in 10-year notes at a high yield of 2.439 percent, the lowest since June 2013. The bid-to-cover ratio, an indicator of demand, was 2.83, versus a recent average of 2.69.
In the 'when-issued' market, the notes were expected to sell at a yield of 2.450 percent.
Indirect bidders, which include major central banks, were awarded 47 percent, close to the 44 percent recent average.
Benchmark 10-year notes were up 11/32 in price with a yield of 2.41 percent. Meanwhile, the 30-year bond rose 21/32 in price to yield 3.24 percent.
On Thursday the Treasury will auction $16 billion in 30-year bonds, which some traders reckon might not fetch strong demand due to their low yields.