Market Report:

As investors continued to pile out of the spread betting firm Plus500, and thousands of its customers were still locked out of their trading accounts, Crispin Odey took advantage of the collapse in the share price to bulk up his holding in the Aim-listed group.

His hedge fund Odey Asset Management was already the second largest investor in Plus500, which shocked the markets on Monday by freezing thousands of accounts to carry out a belated “complete review” of customers’ details to comply with UK money laundering regulations.

However, the news that Mr Odey had bought 1.6 million shares in the broker on Monday, taking its stake to 14.09 per cent, was not enough to stem the sell-off and the stock fell another 66p to 412p, off 45 per cent this week. That left its co-founder and largest investor, Alon Gonen, nursing a paper loss this week of £64m and Mr Odey down about £50m.

The FTSE 100 ended up 26.23 at 6,995.1 even after the latest UK inflation figures showed a slip into deflation, largely caused by a drop in the cost of energy.

The iron ore market was in focus after BHP Billiton head Andrew Mackenzie warned the Australian government that any investigation into the price slump in the market could deter Asian investors. Separately, Citigroup called the top of the iron ore market, sending shares with any exposure southwards.

“We believe the rally in iron ore prices has peaked and reiterate our forecast of sub-$40 [a tonne] prices for the second half of the year,” said Citigroup analysts. The rout was led by BHP Billiton, down 57.5p to 1,405.5p. Glencore was 7.35p lower at 289.65p, Anglo American 16p off at 1,061p and Rio Tinto down 78p to 2,847p.

BTG was in the spotlight after reporting margins and profits “modestly” below estimates. The speciality pharmaceuticals group, which makes products to treat varicose veins and blood clots, as well as snake anti-venom, fell 74.5p to 708.5p.

Topps Tiles provided a bright spot among small cap shares, climbing 12.5p to 133p after forecast-busting results for the year prompted its house broker, Peel Hunt, to raise its estimates.