OAKLAND, Calif.—Federal criminal charges were unsealed Tuesday against the widow of Orlando gunman Omar Mateen, accusing her of aiding and abetting her husband for at least a month before his attack on the Pulse nightclub killed 49 people.

Noor Salman is charged with aiding and abetting Mateen’s provision, and attempted provision, of material support or resources to the Islamic State terror group. Mateen, in calls with police the night of the shooting, made clear he was carrying out a terror attack in support of Islamic State.

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