(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, B&Q 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.

Fresnillo and Randgold Resources were up more than 6%.

Royal Mail shares rose 1% after the firm said it had reached a settlement with French competition authorities.

In July, Royal Mail said it had been informed that one of its businesses in France might have broken competition laws. Royal Mail has now set aside £18m to cover the settlement.

The firm said the recent mild weather had hit demand for winter clothes. It now expects full-year profits of between £88m and £92m, compared with analysts' estimates of £103m.

On the currency markets, the pound was down half a cent against the dollar at $1.6115, and was one-tenth of a cent higher against the euro at €1.2712.