Shares in British online supermarket and technology group Ocado slumped on Tuesday after U.S. partner Kroger said it would close three automated warehouses in January, dealing a heavy blow to the Ocado investment story. Ocado stock closed down 17.4 per cent as the group also said its fee revenue would fall by about $50 million next year as a result of the closures, extending 2025 losses for the shares to 40.5 per cent. The group had a stock market value of 21.7 billion pounds ($28.5 billion)