A Chinese investor walks past an electronic panel showing prices of shares at a stock brokerage house in Hangzhou city, East China's Zhejiang province, July 29, 2015. [Photo/IC]

BEIJING - Chinese shares rose on Wednesday following two-day drops and regulators' promise of support for the market.

The benchmark Shanghai Composite Index climbed 3.44 percent to close at 3,789.17 points. The smaller Shenzhen Component Index went up 4.11 percent to close at 12,823.07 points.

The ChiNext Index, tracking China's Nasdaq-style board of growth enterprises, gained 4.33 percent to end at 2,693.87 points.

China Securities Regulatory Commission (CSRC) said on Tuesday?that it is probing "a massive sell-off" after Monday's sharp dive in the market, and had received whistle-blower reports and market monitoring reports, and had organized inspection and enforcement teams.

China's stock market has seen wild swings in the past six weeks as it plunged some 30 percent from mid-June to early July before rebounding by about 15 percent after regulators took a slew of measures to boost market confidence and avoid risks extending to more sectors.

The Shanghai Composite index lost almost 8.5 percent on Monday, the largest daily loss in eight years, followed by another 1.68 percent loss on Tuesday.

China's regulators have previousely said that "malicious short sellers" will be severely punished, and investigations against short selling and market manipulation have been conducted nationwide, according to the Ministry of Pulic Security.

Wu Yiyao contributed to the story