The Hang Seng Index Monday nose-dived 777.13 points, or 4 percent, to end the day at 18,664.13, the biggest single-day tumble since "9.11" terrorist attack.

China stocks fared worse, with H-share index falling 457 points, or 5 percent, to 8,528, off a low of 8,426.

Turnover rose to 72.44 billion HK dollars (9.29 billion US dollars) from 53 billion HK dollars (6.79 billion US dollars) last Friday.

Blue chips suffered big losses. HSBC, the largest stock by market capitalization, lost 2.5 percent to 133 HK dollars, ahead of the announcement of its annual results later Monday. Its unit Hang Seng Bank fell 0.8 percent to 105.9 HK dollars.

Brokers said the local market was unlikely to find support from HSBC's 2006 results following huge losses on its US mortgage business.

China Mobile, the country's largest telecommunication operator, was down 6 percent at 67.35 HK dollars. China Unicom declined 7.3 percent to 9.13 HK dollars.

All the four sub-indices were lower. The Finance dropped 2.92 percent to 29,645.75. The Commerce and Industry was down 5.02 percent to 9,996.34. The Utilities edged down 1.76 percent to 34, 398.79. The Properties lost 3.58 percent to 22,323.10.

Among property counters, New World plunged 6.6 percent to 16.04 HK dollars. Cheung Kong dropped 4 percent to 89.5 HK dollars. Sino Land dipped 5.5 percent to 16.52 HK dollars.

Among commodity counters, Zijing Mining declined 13 percent to 4.27 HK dollars. Angang was down by 8.5 percent to 11.2 HK dollars. Maanshan Iron pounded 11 percent to 4.27 HK dollars.

Stocks across the region plunged, extending last week's global sell-off. In Tokyo, the Nikkei Index fell 3.34 percent at 16,642, while Singapore and Kuala Lumpur shed more than 4 percent. Shanghai A-shares was down 1.63 percent and B-shares down 6.9 percent. South Korea and Australia stocks also suffered.

Patrick Shum of Karl Thompson Securities said the slump was triggered by strong buying of the Japanese Yen.

With index now falling more than 2,000 points vs record 20,971 hit January 24, talks that market has turned to bear market are growing. But ICEA said in past major bear markets like 1994, 1997 and 2000, valuations shot up to "crazy" levels but current valuation is still reasonable, and "we do not have any unsustainable bubbling event priced in by the market." It thought current fall "is one major pullback" and the index may drop by more than 2,000 points.

SHK Financial's Castor Pang said the market is now oversold and it is ripe for rebound, but investors "should be careful in choosing which stocks to bet for rebound". He advised to buy blue chips such as China Mobile but stay away from small caps despite magnitude of falls.

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