BEIJING, Dec. 4-- Stocks related to free trade zones soared and led Chinese equities to gain for a second day in a row on Wednesday.

The benchmark Shanghai Composite Index advanced 1.31 percent, or 29.09 points, to finish at 2,251.76. The smaller Shenzhen Component Index added 1.28 percent, or 108.30 points, to finish at 8,600.82 points.

Gainers outnumbered losers by 813 to 79 in Shanghai, and by 1,092 to 310 in Shenzhen. Combined turnover was 271.48 billion yuan (44.21 billion U.S. dollars), up from Tuesday's 214.57 billion yuan.

More than 13 companies in relation to free trade zones saw their shares jump by the 10-percent daily limit.

Ministry of Commerce spokesman Yao Jian said on Wednesday that China is planning to establish 18 free trade zones, including the one in Shanghai.

On Monday, the central bank said it recently issued a guideline in offering financial support for the free trade zone in Shanghai.

The guideline was issued to boost the real economy in the zone, provide financial support for cross-border investment and trade and deepen financial reforms, the central bank said in a statement.

A total of 11 companies in relation to the Shanghai free trade zone soared by the 10-percent daily limit, including Shanghai International Port, Shanghai Lujiazui Finance & Trade Zone Development, Pudong Road & Bridge Construction, CTS International Logistics and Orient International Enterprise.

Stocks of other sectors -- including shipping, agriculture, telecommunication equipment, tourism and automobile -- also gained. The leading losers were in the sectors of petroleum and medical appliances.

Shares of six sapphire producers and iPhone handset component suppliers, including TDG Holding and Zhejiang Crystal-Op Tech, also saw their shares jump by the 10-percent daily limit, amid reports claiming that Apple's iPhone 6 might be equipped with a sapphire glass screen display.

Ai Tangming, a Beijing-based stock market analyst, said Wednesday's gains indicated that the impact of the reform plan for the initial public offering (IPO) system has significantly diminished and market sentiment is increasingly optimistic.

The China Securities Regulatory Commission on Saturday unveiled the reform plan to the IPO system, a major step in introducing a system of registration for IPO issuances to replace the current administration approval mechanism.