Federal prosecutors have charged a Russian national in a wide-ranging conspiracy designed to undermine U.S. elections including next month’s midterms, according to charges unsealed Friday, in the first-known case targeting the November campaign.

In a 73-page affidavit accompanying the charges, authorities described Elena Alekseevna Khusyaynova, 44, of St. Petersburg, Russia, as the “chief accountant” of a broad online disinformation campaign designed to inflame U.S. public opinion and exacerbate tensions within U.S. society

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