(Corrects 3rd paragraph to clarify Murcia has not requested aid) By Karen Brettell NEW YORK, July 23 (Reuters) - U.S. Treasuries yields fell to new record lows on Monday as concern that the euro zone's debt crisis is spiraling out of control led investors to seek out the relative safety of U.S. debt. U.S. bond yields have fallen this month as economic growth loses traction and as investors increase bets that the Federal Reserve will launch new stimulus in a bid to reignite growth, and encourage new lending. New fears over Europe's debt crisis on Monday sparked a rush to safe haven bonds after Murcia looked set to become the second Spanish region to seek help from the central government, sending Spain's debt yields to record highs. "The market is responding to the ongoing stresses in Europe," said Chris Ahrens, interest rate strategist at UBS in Stamford, Connecticut. The eastern Valencia region of Spain said on Friday it needed help and media reported more regions are likely to do the same.. A planned visit by Greece's troika of creditors on Tuesday added to nervousness over the region, with many investors continuing to fear a Greek exit from the euro zone, for which markets are unprepared. Greece has slid further off course from its fiscal and economic reform targets, and the man in charge of privatizing state enterprises resigned last week in despair at delays. The European Central Bank has also stopped accepting Athens' bonds as collateral for lending to Greek banks. With no news expected to show a resolution to the region's woes, Treasuries are likely to remain well bid. "There's no imminent positive event that people can think of," said Suvrat Prakash, an interest rate strategist at BNP Paribas in New York. U.S. Treasuries have also benefited from a relative scarcity of high-grade debt, as well as expectations that the Fed will further support bonds through new debt purchases as the economy slows. Data on Friday is also expected to show that U.S. gross domestic product grew at disappointing pace of only 1.4 percent in the second quarter, according to the median estimate of 60 economists polled by Reuters. "All the data in the last few weeks have pretty much confirmed that the U.S. economy has slowed down after some euphoria at the start of the year," said BNP's Prakash. "On Friday this GDP number should confirm it." This sentiment is likely to aid the Treasury's sales of $99 billion in new two-year, five-year and seven-year debt this week, starting with a $35 billion sale of two-year notes on Tuesday. Benchmark 10-year note yields have fallen a full percentage point since March, when they traded as high as 2.40 percent. They traded as low as 1.3977 percent on Monday, 4 basis points below the previous low of 1.44 percent first reached on June 1. The notes were last up 9/32 in price to yield 1.43 percent. Thirty-year bond yields fell as low as 2.4766 percent, below its previous low of 2.51 percent also reached on June 1. They were last up 1-3/32 in price to yield 2.50 percent. (Editing by Andrea Ricci)