Social media complaints started surfacing around noon ET Friday.
Chase’s technical support confirmed on Twitter that “some customers are experiencing difficulties logging in.” Other consumers mentioned issues with Chase’s mobile app.
Capital One also said on Twitter that it was experiencing “credit card online access issues.”
Both companies could not immediately be reached for comment on the nature of the issues. The U.S. Department of Homeland Security and Federal Bureau of Investigation told CNBC they had not seen anything suspicious.
JPMorgan Chase and Capital One shares were trading 0.7 and 1 percent higher on Friday, respectively.
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