Experts say return of margin traders a boost but risky

Margin traders are making a comeback in the Chinese stock market, prompting analysts to warn about a new "bubble" despite last summer's turmoil.

In less than two months, the value of outstanding margin loans at the Shanghai and Shenzhen stock exchanges increased rapidly by more than 20 percent, with total value exceeding 1.16 trillion yuan ($183 billion) as of Nov 12, the highest level since September.

The surge in margin trading, which describes stock buying through borrowed money from securities firms, is considered a sign of recovering market sentiment. Money has been flowing back to China's battered stock market after the benchmark Shanghai Composite Index rebounded by more than 20 percent from its August low.