Chinese shares dropped by more than 2 percent at midday Friday on profit-taking, said analysts.

The benchmark Shanghai Composite Index slid 2.27 percent, or 71.47 points, to 3,076.28 in the morning session.

The Shenzhen Component Index dropped 3.37 percent, or 461.07 points, to close the morning session at 13,223.87.

The stocks opened slightly lower in the morning and rose for a while when two oil heavyweights surged on expectations that the government would raise fuel prices. PetroChina, the country's largest oil company, once surged more than 4 percent in the morning trade.

But share prices began plunging at around 11 a.m. as investors were split on the market trend and many sold stocks to take profits.

Industrial and Commercial Bank of China Ltd., the nation's largest lender, slid more than 2.7 percent to 4.64 yuan (70 U.S. cents). Vanke, the country's biggest developer by market value, tumbled more than 3.3 percent to 8.87 yuan.

PetroChina rose 2.83 percent to 13.1 yuan. Sinopec, Asia's largest refiner by capacity, was up 0.95 percent to 9.58 yuan.

Analysts said investors were worried about the inflation and policy risks as the country's consumer price index, a major gauge of inflation,hit a 25-month high of 4.4 percent in October.