In a news conference on Wednesday, Sergeant Tommy Thompson said: "She was not in a position to give consent to any of this".
The lawyer for the family of a 29-year-old Native American woman who has been in "a completely vulnerable state" after almost drowning over a decade ago said Tuesday that "the baby boy has been born into a loving family and will be well cared for", Arizona Family reported.
Hacienda HealthCare, who run the facility where the woman was attacked backed the development, saying: 'As a company, we welcome this development in the ongoing police investigation'.
Thompson declined to say if police were looking at visitors to the health care center in addition to employees, and he would not specify whose DNA has been obtained or is being sought.
The centre said a warrant was served by police on Tuesday, as authorities try to find out how the woman became pregnant.
The investigation prompted outrage nationwide last week after KPHO revealed a 29-year-old Native American woman living in a yearslong vegetative state had been impregnated at the facility.
Martin Solomon, a personal injury attorney in Phoenix whose clients are mostly vulnerable adult victims of abuse and neglect, said a lawyer representing this woman should call for all pertinent medical records, a list of current and ex-employees and any past litigation involving Hacienda.
On the same day that the baby boy was born, officers responded to a call that an infant had "coded" and was in "distress" with troubles breathing.
Tribal chairman Terry Rambler said: "On behalf of the tribe, I am deeply shocked and horrified at the treatment of one of our member".
And he added staff could face charges if it emerges they did know about the pregnancy and failed to act.
"When you have a loved one committed to palliative care, when they are most vulnerable and dependent upon others, you trust their caretakers".
Alejandro Benally, Chief of the San Carlos Apache Police Department also had a statement included in the letter, "At this point, this matter falls under the jurisdiction of the Phoenix Police Department". Staff have denied knowing about it until the birth.
Hacienda CEO Bill Timmons stood down on Monday amid the deepening scandal.
Board member Gary Orman said the facility "will accept nothing less than a full accounting of this absolutely horrifying situation".
The department of health ordered Hacienda to implement "heightened safety measures", spokeswoman Melissa Blasius-Nuanez said.
The case is "disturbing, to put it mildly", said Jon Meyers, executive director of The Arc of Arizona, an advocacy group for people with intellectual and developmental disabilities.