Millions of customers with retirement funds invested through Fidelity Investments could be at risk following the revelation of a damaging internal company memo, The San Francisco Chronicle reports.

Written by Tom Strotman, a director in customer support services at Fidelity the leaked note depicts a hypothetical scenario whereby a customer's 401(k) account is accessed and emptied by an unauthorized caller. It claims that this sort of activity actually occurs and states that Fidelity's risk-management department "has had to make many unpleasant calls to customers in situations like the one described above."

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