SACO, Maine — Sweetser announced Friday that sensitive information of approximately 22,000 current and former clients was compromised in June.

The nonprofit community mental health provider notified potentially affected current and former clients by mail on Friday, October 25, that the breach potentially included client names, addresses, dates of birth, telephone numbers, Social Security numbers, health insurance information and identification numbers, driver’s license numbers, Medicare or Medicaid information, payment or claims information, diagnostic codes, and information regarding medical conditions and treatment.

According to a release Friday, the organization is not aware of any unlawful activity occurring as a result of the breach.

Sweetser detected unusual activity in its "email environment" on June 24, 2019, and soon learned that a third party may have gained access to an employee's email account, spokeswoman Susan Pierter wrote in a release.

Sweetser secured the account and began investigating with a digital forensics firm. They determined in September that employee email accounts were subject to unauthorized access from approximately June 18 to June 27, 2019.

The organization reported the incident to the FBI and the U.S. Department of Health and Human Services Office for Civil Rights, which is investigating.

"The privacy and protection of private information is a top priority for Sweetser," the organization said in the release."Sweetser deeply regrets any inconvenience or concern this incident may cause."

The organization offers behavioral health and crisis intervention services in residential and outpatient environments to adults and children statewide.

Sweetser has established a toll-free call center to answer questions about the breach and related concerns at (833) 444-4458. The center is open weekdays from 8 a.m. to 5 p.m. Eastern Standard Time.

In addition, the organization is offering complimentary identity protection services to individuals whose Social Security numbers were potentially compromised.

Sweetser's website offers additional information for clients to protect themselves.

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