HANG Seng index futures saw a frenetic day of trading as the cash market punctured supports on a 279-point dive. The cash market closed at 7,789 as institutional investors in Hong Kong and abroad gave up on territory stocks and cashed in. Index futures volume was a heavy 25,166 contracts in December with 55 in January. The December futures closed 230 points down to 7,750, a discount on the cash of almost 40 points. January futures were down 240 points at 7,760. Fimat Futures said sellers were Nomura, with more than 2,000 contracts, along with Jardine Fleming at 7,780. Main buyers were Morgan Stanley, with more than 2,000 contracts, and Credit Lyonnais. Index options saw front month implied volatility rise sharply to 34 per cent or 35 per cent at the money. The volume was 2,931 lots. Jardine Fleming said: 'The volatility level proved to be too expensive for the hedgers and they sold December out-of-the-money calls instead. 'Premium sellers took the opportunity to sell the December 7,600 puts.' The open interest for Thursday in futures was 40,884 contracts in December, 258 contracts in January and 459 contracts in March. In December there were 15,471 calls and 15,874 puts, in January there were 236 lots and 1,817 lots respectively and in March there were 3,373 and 2,736 respectively.