Nervous investors sparked yet another sell-off on the London market today as the FTSE 100 Index plunged towards the 4300.00 barrier.

Continued fears about accounting standards and the health of the United States economy resulted in a host of key blue-chip stocks falling in early trading.

By mid-morning the Footsie was hovering close to the lows following the September 11 attacks, down 79.90 points at 4340.20.

A three per cent fall on the Dow Jones Industrial Average last night, after downgrades on both General Motors and Ford, set the tone for trading in the City.

Banks, oil and pharmaceutical stocks all slid, with mobile phone giant Vodafone the notable exception.

Vodafone edged up 1.5p to 89.75p as dealers crossed their fingers and hoped for a positive start to trading on Wall Street later this afternoon.

The Dow was expected to open about ten points up after yesterday's heavy fall which saw it close below the 9000 barrier.

Tom Hougaard, of financial bookies City Index said: "We are simply sitting and waiting for the US to open and then we can ascertain if there is more to come or if the selling has finally been exhausted."

Of the big fallers, GlaxoSmithKline was down 37p at £12.33 and AstraZeneca fell 85p to £23.80 while Shell dipped 7p to 469p and BP fell 10.5p to 526.5p.

In the banking sector, Barclays slipped 12.5p to 469.5p, HSBC dropped 9p to 732p and Royal Bank of Scotland drifted 45p to £16.50.

Among corporate news there was little to lift the mood as retailer JJB Sports warned profits would be hit by sales pressure.

The group fell by almost 30 per cent, or 91.5p to 220p, after reporting like-for-like sales growth of just one per cent in the 23 weeks to July 7.

Former Footsie stock Autonomy dived 35 per cent after warning second quarter revenues would fall below the first quarter. Shares fell 71.5p to 133.5p.