(Close): London shares closed at their lowest level for a year as concerns about the eurozone economy resurfaced.
Weak German export data reignited fears the eurozone may go back into recession, while Chancellor George Osborne warned that the UK was not immune from events on the continent.
The FTSE 100 closed the day down 50.39 points, or 0.8%, at 6,431.85.
US shares also suffered as fears of a global slowdown spread, with the Dow Jones index down 260 points, or 1.5%.
The oil price also fell, with Brent crude down more than 1% at $90.32 a barrel, its lowest level for more than two years. US light crude fell by 2% to $85.82 a barrel.
In London, BQ owner Kingfisher led the way down, falling 5%, followed by housebuilder Persimmon, down 3.5%.
Firms associated with travel continued to suffer as worries over the potential impact of the Ebola virus continued. Shares in British Airways owner IAG fell a further 3%.
Shares in Vodafone fell 3.4% after Nomura cut its rating on the company to “reduce” from “neutral”, while in the FTSE 250 shares in N Brown sank more than 13% after the catalogue retailer issued a profit warning.
On the upside, mining firms enjoyed a strong day, boosted by a rise in the prices of metals.