HUNDREDS of millions of pounds have been wiped off the value of East Lancashire's Stock Exchange-quoted companies as share prices have plummeted in the aftermath of the terrorist attacks on America.

With all of Britain's top businesses reporting falls in their share price, the slump has spread to virtually all companies in the area.

The FTSE 100 Index closed at a four-year low of 4359, down 197 points on the day, yesterday as nervous investors joined the rush to sell.

One of the most dramatic falls has been at Lancashire-based travel giant Airtours whose share price dropped by 27 per cent yesterday to a year's record low of 98.5p.

Amid fears for the travel and tourist industries, the company has seen more than £770 million wiped off its market capitalisation since mid-August. The company is now valued at £483million.

Airtours issued a trading statement late yesterday when it admitted that the USA bombings would cost the company £10million in lost profits up to the end of September.The company said: "In the first 49 weeks of our fiscal year, the Group was on track to deliver record profits. Our first priority following the tragic events of September 11 was the safety and repatriation of our customers and staff.

"The immediate impact on our business of this disruption is estimated to be in the region of £10million."

Airtours said it was too early to predict the full impact of the terrorist attacks on its business. "Our previous experience of booking patterns during the Gulf War suggests that leisure travel markets are robust and that the disruption of bookings is more a timing issue than a loss of overall demand," said the company.

Shares in jet engine-maker Rolls-Royce, which employs more than 1,000 people at its Barnoldswick factory, recovered in late trading to add 2p to its share price of 128p. The company is now valued at £2,048 million -- down £1,312 million on mid-August. With airlines and plane-builders announcing tens of thousands of redundancies, there is turmoil throughout the entire industry with uncertainty over future orders.

BAE Systems, with 10,000 Lancashire workers at Samlesbury and Warton, had been holding out against the general loss of confidence in the industry, buoyed by its military contracts and its 20 per cent stake in the successful Airbus programme.

However, the Stock Market slump caught up with the company on Friday when its share price fell by 5.25p to 299.75p, a 1.7 per cent fall. The conservatory roof manufacturer now has a market valuation of £178 million. In mid-August, it was worth £330 million. Interlink Food, the Blackburn-based cakes and confectionery company, saw its share price pegged back to a year's low of 252p, down 16p on the day.