BEIJING, July 3 -- The Chinese stock market experienced a rollercoaster ride on Friday and extended its losing streak with major indexes registering further losses, evidence that investors still lack confidence despite easing measures from the government.

The benchmark Shanghai Composite Index dived 5.77 percent to finish at 3,686.92 points, falling below the psychological threshold of 3,700 points. Since June 12, the index has dropped more than 28 percent.

The index lost more than 6 percent within the first hour of trading on Friday, bounced back from morning losses in the early afternoon, but closed sharply lower suffering from a round of heavy sell-off.

The tech-heavy Shenzhen Component Index plunged 5.25 percent to close at 12,246.06 points, with the ChiNext Index, tracking China's Nasdaq-style board of growth enterprises, losing 1.66 percent to end at 2,605.28 points.

Shares fell across the board in most sectors, with utilities, steel, cement and transportation companies leading the losses.

Losers outnumbered winners by 886 to 37 in Shanghai, and by 1,240 to 95 in Shenzhen. The stock decline continued despite a string of supporting measures from the authorities.

After the tumble on Wednesday, the Shanghai and Shenzhen bourses announced a roughly 30-percent cut in stock transaction fees. Late on Thursday, the securities watchdog also announced it will investigate suspected manipulation of the stock market.

Share financing from brokerages and over-the-counter helped propel the Shanghai Composite Index to double within a year by June 12, but the recent slump has fuelled worries that the year-long bull run is near its end. However, many long-term investors and analysts held that the market correction has created good investment opportunities.

Following the government's regulation of over-the-counter share financing, the market witnessed plunges in past weeks. But after the market tides over the recent volatility, a new rally is around the corner, said Sun Xiwei, a senior analyst with CITIC Securities.

"A raft of supportive monetary measures has been rolled out and China's economic growth has stabilized, so blue-chip companies and shares related to the Internet and state-owned enterprise reform enjoy sunny prospects, said Shi Bo, with South China Fund, a major equity fund management firm.