The New York Stock Exchange this month. (AP Photo/Mark Lennihan)

Stocks plunged Wednesday in rocky trading, closing down on a fourth straight day of losses amid a stretch of volatility in international trading that routed investors to the refuge of government bonds.

The Dow Jones industrial average closed down 173 points, or about 1 percent, after churning throughout the day. It had plummeted more than 300 points within the first 10 minutes of trading, then stuttered back up to regain half those losses. By midafternoon it had plunged again, dropping 460 points at the session low.

Several other major indexes were also sharply down, only to regain some losses by closing bell. The Standard & Poor’s 500 closed down around 1 percent. The tech-heavy Nasdaq climbed back to close only slight down.

Stocks have been suffering from a period of rocky sell-offs lately, much of it tied to growing worries over weakening economies in Europe and Asia. Federal Reserve officials have said that a loss of momentum in global growth could hurt American exports and the broader economy, and some investors have begun looking for the exits.

The global slowdown helped demand for oil continue its downward slide, with prices for a barrel of the benchmark grade settling in around four-year lows. Also weighing on the markets Wednesday was a big drop in retail sales, which fell 0.3 percent last month, far more than analysts had expected.

The Chicago Board Options Exchange Volatility index, a “fear gauge” of investor apprehension, climbed to one of its highest points since late 2011. Nervous investors helped drive yields on 10-year U.S. Treasury bonds, which started the year near 3 percent, to below 2 percent for the first time in 16 months.

Stock markets in France, Italy and Greece tumbled in the midst of critically low inflation in Europe, while investors clamoring for safety pushed German government bonds, believed to be safer than stocks, to record-low yields.

The unprecedented spread of the Ebola virus has contributed to investor uncertainty, leading to sell-offs of stocks like cruise companies and airlines. United Continental Holdings tumbled more than 6 percent, while American Airlines was off nearly 5 percent.

The Dow has fallen 2.5 percent, nearly 400 points, since the beginning of the year. The Nasdaq and S&P 500 are still in positive territory.

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