STOCKS advanced yesterday on the back of a massive futures-led rally just before lunch. The Hang Seng Index gained 171.65 points to close at 9,618.08, up 1.82 per cent. Volume was also much firmer at $4.28 billion. Brokers said a huge push in the futures market, which saw the index rise by 100 points just five minutes before the lunchtime close, was caused by a large buyer coming on to the market. Traders said that a large American brokerage without a seat on the floor had 2,500 futures contracts to buy through the day. Sources said that Warburg, Hoare Govett and Jardine Fleming were the three main brokerages on the bid side for the brokerage, and had been steadily buying contracts in the morning against strong selling from Morgan Stanley and Nomura. Just before lunch the futures market hit the 9,600 level, which triggered an order from Credit Lyonnais, reportedly for 250 contracts. But because of the limited time left to trade before the market closed for lunch, a buying frenzy ensued, pushing the index up to touch the 9,650 mark. In the afternoon session, the cash market picked up to trade in line with the futures but at a steep discount, and futures remained strong as Hong Kong buyers were lured into the market. ''The buying was predominantly local, especially because it exploded in the second session, which is when most of the US accounts leave their desks,'' said an American trader. The market was helped by signs that China and Britain had come close to an agreement, which saw the market rally spectacularly in London overnight on Tuesday. Even though the first reports of an agreement relayed through a wire service were not entirely correct, analysts said the news was encouraging. However, those gains were eroded in London last night with large falls on the back of poor company earnings in Hong Kong. Meanwhile, a broker for Credit Lyonnais Securities in London said that although the Cathay Pacific results were in line with forecasts, they were still disappointing. He added that the large 10 per cent drop in HAECO shares also affected sentiment. Shares in Swire Pacific held steady at $61.75 yesterday, but it has been one of the worst-performing blue chip shares over the week on concern that its profits would not be outstanding. However, a rumour around the market was that a major British institutional shareholder had put eight million shares on the market during the past week. According to the rumour, five million shares had been sold so far, leaving three million still to sell. HAECO was one of the worst casualties after its result announcements. The blue-chip counter fell 11 per cent to $41.90, a $5.20 drop, in strong trading as investors dumped the stock in one of the largest falls seen by a Hang Seng Index constituent this year. Brokers said attention would focus on the results of Swire, due to be released today, and the likely US interest rate increase next Tuesday when the Federal Reserve Open Markets Committee meets. Analysts are expecting an increase of between 25 and 50 basis points, which should see the Hong Kong market stay in its current trading range between 9,450 and 9,750. ''The market is capped by the 200-day moving average around 9,745 and can't break out of it,'' said a derivatives salesman. Television Broadcasters (TVB) also fell, dropping 40 cents to close at $34.40. The counter has been bid up on speculation that British media company Pearsonmay purchase a stake in the company. But some analysts think Pearsonmay not pay as much as $40 for each TVB share, as has been speculated in some British newspapers.