U.S. stocks tumbled to start 2016, as a rout in Chinese equities renewed concern that an economic slowdown there will damp global growth.

Investors returning to the market after the New Year holiday faced a worldwide selloff sparked by weak factory data in China, while a reading that showed the fastest contraction in U.S. manufacturing in six years bolstered anxiety that slowing growth in the world’s second-largest economy is spreading. A flareup in tension between Saudi Arabia and Iran added to the unease.

The Standard & Poor’s 500 Index fell 1.5 percent to 2,012.98 at 4 p.m. in New York, after sliding as much as 2.7 percent, for its worst start to a year since 2001.

Trading was halted in China after a 7 percent drop in the CSI 300 Index of large-capitalization companies listed in Shanghai and Shenzhen amid deteriorating manufacturing data. Chinese policy makers, who went to unprecedented lengths to prop up stock prices during a summer rout, are trying to prevent financial-market volatility from weighing on economy set to grow at its weakest annual pace since 1990.

Source : Bloomberg