HONG Kong stocks continued their slide in London overnight, after the Hang Seng Index had fallen by 793.43 points, its biggest drop since the October 1987 crash. Frantic selling saw Hang Seng stocks dive another 232 points to 11,142 by the close at 11.30 pm (Hong Kong time). The biggest losers were Dairy Farm International, which fell 30 cents, or 3.85 per cent, to $14.80, and Cathay Pacific, which was down 50 cents, or 3.52 per cent, to $13.70. None of the 22 Hong Kong stocks listed in London ended the day ahead. The index had spiralled to 11,374.5 at the close here yesterday afternoon, mostly because of political and economic concern about China. Amid growing evidence of possible social unrest on the mainland, international investors began running for cover when the market opened. The sharp drop on the local market was the biggest since the 1,120.7-point tumble on Black Monday in October 26, 1987, when financial markets around the world crashed. Having ignored politics during the bull run, investors are showing signs of nervousness about events here and in China. Analysts said their clients were becoming worried by official reports in China's media about social unrest, problems with inflation and the succession of power when octogenarian leader Deng Xiaoping dies. Dealers held little hope for a rebound today and some believe the Hang Seng could dive another 1,700 points before finding any strong support. ''I think the market closed at its lowest point and there was no real support at the close,'' said Vickers Ballas director Barry Yates. Turnover, which has soared recently on a flood of foreign money, hit $13.07 billion. This is the third-highest behind the turnover on Wednesday and Tuesday. Mr Yates said political factors, which had been ignored by investors for months, finally came back into the picture yesterday with devastating effects. ''Suddenly, uncertainty found its way on to traders' screens on what the Chinese economy is doing,'' he said, adding a decline to 10,000 points was possible. Mr Yates said investor sentiment was also affected by reports that Chinese authorities were rushing emergency supplies of grain to eight provinces and three major cities to prevent social unrest. He said these reports only served as a catalyst for investors to bail out of the market. PBI Securities sales director Ivan Leung said it was important to remember that major corrections had hit the market in recent months as it climbed to new heights and investors should not see it as unhealthy. He said, for example, the market surrendered 290.8 points on November 3 after it had pierced the 9,600-point barrier and dropped 290.5 on December 21 after moving through the 10,800 mark. ''I'm not so bearish at this level because I think there's good support at 10,880,'' he said. The index is still trading higher than it was just two weeks ago and it has jumped 18.4 per cent, or 1,764.81 points in the past month. Baring Securities director James Osborn said many investors took advantage of the political and economic concerns about China to take profits made over the past month. ''We didn't see huge overseas selling,'' he said. ''But the market ran up so fast, so quickly that people were running for the door.''