The police in Phoenix have opened an investigation into allegations that a woman in a vegetative state at a private nursing facility was sexually assaulted and gave birth to a child last month, the authorities said Friday.

Sgt. Tommy Thompson, a spokesman at the Phoenix Police Department, said that detectives were looking into the case at the facility, which provides long-term care for people with intellectual disabilities. Sergeant Thompson declined to elaborate on how long the investigation had been open or other specifics about the case, which was reported Thursday by KPHO-TV, the CBS affiliate in Phoenix. The woman has not been publicly identified.

A spokeswoman at the Arizona Department of Health Services said that the agency was aware of the allegations and had sent inspectors to check on patients at the institution, which is about seven miles south of downtown Phoenix. The facility is part of Hacienda HealthCare, which its website describes as an organization for some Phoenix-based health care programs and services.

“During this time, the agency has required heightened safety measures be implemented at the facility, including increased staff presence during patient interactions; increased monitoring of the patient care areas; and increased security measures with respect to visitors at the facility,” the spokeswoman, Melissa Blasius-Nuanez, said on Friday.