San Francisco (CNN Business) A federal inquiry has been opened into Google's efforts to collect health data on millions of Americans through its "Project Nightingale" program.

The Department of Health and Human Services' Office for Civil Rights opened the inquiry on Tuesday, The Wall Street Journal reported.

The office "would like to learn more information about this mass collection of individuals' medical records with respect to the implications for patient privacy under [the Health Insurance Portability and Accountability Act of 1996 or HIPAA]," director Roger Severino said in a statement to CNN Business.

Google GOOG The data collection is being done through a new partnership betweenand Ascension, one of the country's largest nonprofit and Catholic health systems. The two companies confirmed they were working together to analyze patient data and give health care providers new insights and suggestions for patient care. The Wall Street Journal was the first to report on the project on Monday.

The partnership between Google and Ascension will integrate Ascension's different areas of health data in the cloud. Google said in a blog post on Monday that the project was a "business arrangement to help a provider with the latest technology, similar to the work we do with dozens of other healthcare providers."

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