Sports Direct shares went into a tailspin yesterday and tumbled to the bottom of the FTSE 100 as its shares tanked by 12pc after a slowdown in sales and a report by The Guardian exposing dubious working conditions at the company.

The sportswear retailer has been accused by The Guardian of operating “gulag” warehouses that pay below the minimum wage. It was alleged that staff were docked pay for being late but had to be at work for extra time while they underwent body searches.

Sports Direct also lashed out against accusations that 80 percent of its warehouse staff were on zero hours contracts.

“To be clear, no warehouse workers are on ‘zero hour’ contracts, all have contracted hours with the agencies”, Keith Hellawell, chairman of Sports Direct told The Daily Telegraph.