Oil and US share prices tumble over fears for global economy

S&P 500 suffers its worst day since September as new data showing American fuel stockpiles have hit record levels saw Brent crude fall to below $30 a barrel

US stocks fell heavily on Wednesday, with the Standard & Poor's 500 falling 2.5% to take the index below 1,900 points for the first time since September, due to growing concerns about the falling oil price, which dipped below $30 a barrel for the first time in nearly 12 years.

The S&P 500, which closed at 1,890 points, suffered its worst day since September and has fallen by 10% since its November peak taking it into "correction" territory, something that has not happened since August 2014.

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