US police have served a search warrant to get DNA from all male employees at a care facility in Arizona where a patient who was in a vegetative state gave birth.
Hacienda HealthCare, the company which owns the facility in Phoenix, said that it welcomed the DNA testing of workers.
"We will continue to cooperate with Phoenix Police and all other investigative agencies to uncover the facts in this deeply disturbing, but unprecedented situation," the company said.
Local news website Azfamily.com first reported the woman, who had been in a vegetative state for more than 10 years after a near-drowning, delivered a baby on December 29.
Officials with the San Carlos Apache tribe said the 29-year-old woman was a member of the tribe, whose reservation is in south-eastern Arizona about 134 miles east of Phoenix.
The woman was still in a vegetative state when she gave birth, the tribe said. It is unclear if staff members at the facility were aware of her pregnancy until the birth.
"On behalf of the tribe, I am deeply shocked and horrified at the treatment of one of our members," tribal chairman Terry Rambler said.
A lawyer for the woman's family said in a statement that her family was outraged at the "neglect of their daughter" and asked for privacy.
"The family would like me to convey that the baby boy has been born into a loving family and will be well cared for," Phoenix attorney John Micheaels said.
San Carlos Apache police chief Alejandro Benally said Phoenix police "will do all they can to find the perpetrator".
A spokesman for Hacienda HealthCare said investigators served a search warrant to obtain DNA samples from all male workers.
In a statement, board member Gary Orman said the facility "will accept nothing less than a full accounting of this absolutely horrifying situation".
"We will do everything in our power to ensure the safety of every single one of our patients and our employees," Mr Orman said.
Hacienda CEO Bill Timmons stepped down on Monday. The decision was unanimously accepted by the provider's board of directors.
Arizona Gov. Doug Ducey's office has called the situation "deeply troubling."