About 5.6 million patients and employees at Ascension were affected by a cyberattack earlier this year, according to a report filed with the federal government.
Ascension will notify affected individuals over the next two to three weeks, in addition to providing credit monitoring and identity protection services, the health system said in a Thursday statement.
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Ascension reported unusual activity on its systems in May and later confirmed it as a ransomware attack. System outages in the wake of the attack forced Ascension to cancel some elective procedures and divert emergency cases to other facilities. The health system restored electronic health records in June and said it believed personal data may have been compromised.