China benchmark stock index falls nearly 7 percent in second day of global sell-off

China's main stock index fell nearly 7 percent in early trading Tuesday in the second day of a sell-off in global markets on worries about the state of the U.S. economy.

The Shanghai Composite Index dipped to its lowest level in five months early in the day before regaining ground to end morning trading at 4,714.30, down 4.1 percent.

The Shenzhen Composite Index dipped as much as 6 percent in early trading but was down 4.1 percent by midday.

The drop tracked second-day losses in other major Asian markets. Japan's benchmark Nikkei 225 index has dropped more than 4 percent Tuesday, and Hong Kong's Hang Seng Index is off around 8 percent near …