On Tuesday, the San Carlos Apache Tribe said the 29-year-old woman is a member, according to statement provided to 12 News.
An investigation is underway by Phoenix Police, as controversy mounts over the incident.
In a statement sent to local media, Gary Orman, executive vice president of the board at the private healthcare company, said it "will accept nothing less than a full accounting of this absolutely horrifying situation, an unprecedented case that has devastated everyone involved, from the victim and her family to Hacienda staff at every level of our organization".
"On behalf of the Tribe, I am deeply shocked and horrified at the treatment of one of our members", said San Carlos Apache Tribe Chairman Terry Rambler.
On Monday, longtime CEO Bill Timmons resigned from Hacienda after reports of the December birth surfaced last week.
It has been learned that a woman in a vegetative state at a Phoenix-area nursing facility was sexually assaulted after giving birth to a baby boy on Saturday. It's also unclear if staff members at the Hacienda de Los Angeles facility were unaware of the pregnancy until the birth. Since entering the hospital's care, she's been in a complete coma. According to agency documents, Hacienda HealthCare later corrected facility "deficiencies" that contributed to the incident. Sadly, one of her caretakers was not to be trusted and took advantage of her.
In the statement, DHS spokesperson Melissa Blasius-Nuanez said the agency immediately initiated an onsite complaint investigation to "ensure the health and safety of the patients and ensure the facility is in compliance with all state laws and regulations".
A spokesman for Arizona Governor Doug Ducey said the reports were "deeply troubling" and that the state was re-evaluating its contract and regulatory authority over Hacienda Healthcare to tighten up patient safety measures. In January 2018, state investigators said the issues "have been corrected", People reported. They declined further comment on Tuesday.
The source added the patient required around-the-clock care and many would have access to her room.
Hacienda describes itself as Arizona's "leading provider of specialised health care services for medically fragile and chronically ill infants, children, teens, and young adults as well as those with intellectual and developmental disabilities". "Whether it's an employee or someone from the outside, the facility has an obligation to protect residents".