Tension increased in Ukraine as pro-Russian rebels shot down two Ukrainian fighter jets.
In the Middle East, meanwhile, Israeli forces continued to pound Gaza on Wednesday, meeting stiff resistance from Hamas Islamists and sending thousands of residents fleeing.
U.S. Secretary of State John Kerry, however, said on a visit to Israel that ceasefire talks had made some progress.
In late morning trading, benchmark 10-year U.S. Treasury notes were up 1/32 in price to yield 2.46 percent, down from 2.47 percent earlier. The 30-year Treasury bond was up 4/32 in price, pushing the yield down to 3.25 percent. On Monday, U.S. 30-year Treasury bond yields fell to their lowest since June 2013.
U.S. Treasurys rose on Tuesday in the wake of a tame CPI reading.
"The latest numbers will admit a pause in the gathering strength of inflation, and will not deter the 'doves' from claiming that inflation is transitory,'' said Thierry Albert Wizman, interest rates and currencies strategist at Macquarie in New York.
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But he believes U.S. annualized core inflation is trending higher, with averages of 1.6 percent in the fourth quarter of 2013, 1.8 percent in the first quarter this year, and 2.6 percent in the second quarter.