Citigroup Inc.'s board has hired an outside law firm to help with its investigation into allegations of fraud in its Mexico unit Banamex, according to media reports. The third-largest bank by assets has hired longtime law firm Willkie Farr & Gallagher, after it was revealed in February Banamex lost up to $400 million on loans. The losses involved Mexican oil-services company Oceanograf�a SA and the Mexican government is currently doing their own investigation into the matter. Citigroup director James Turley will serve as the board's point person on the investigation. Turley, the former CEO of Ernst & Young, joined the bank last year and is chairman of the board's audit committee.

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