NEW YORK -- U.S. Treasuries prices rose on Monday with benchmark yields falling to four-month lows as investors worldwide scrambled for low-risk assets and dumped stocks and risky investments due to worries that China's problems will hurt the global economy.

A near 9 percent drop in Chinese stocks on Monday triggered heavy selling in commodities and other stock markets. The latest market turbulence reduced expectations the Federal Reserve would raise interest rates in September, which some traders reckoned could further undermine investor confidence.

The global stock market rout began after Beijing surprised investors on Aug. 11 when it devalued the yuan, a move that sparked fears about a "currency war" in which nations seek to make their exports cheaper against their trading partners.

"The China devaluation opened up Pandora's Box. We're seeing the spillover effects into commodities and emerging markets," said Mike Cullinane, head of Treasuries trading at D.A. Davidson in St. Petersburg, Florida.

Worries about China, the world's No. 2 economy and a huge importer of raw materials, have stoked a dramatic drop in oil prices and other commodities. The stock markets of developing economies that rely on commodities exports have tumbled with the MSCI emerging market index hitting a six-year low.

In this jittery climate, investors rushed into the perceived safety of U.S. Treasuries, German Bunds, yen and gold, analysts said.

On heavy trading volume, benchmark 10-year Treasuries notes were up 13/32 in price after rising more than 1 point earlier. The 10-year yield was last 1.99 percent, down 6 basis points, after falling to four-month trough of 1.905 percent.

The two-year note yield fell to a 6-1/2 week low as traders reduced their expectations of a September rate increase. It was last down 5 basis points at 0.576 percent.

In the futures and over-the-counter markets, the drop in money market rates implied traders now see one-in-four chance the Fed would raise rates next month and a 50 percent chance of a rate hike in December.

Analysts said the risk aversion among investors should bode well for this week's auctions of U.S. government debt.

The Treasury Department will sell $90 billion in coupon-bearing debt next week, including $26 billion in two-year notes, $35 billion in five-year notes and $29 billion in seven-year notes