PHOENIX – Phoenix police arrested a 36-year-old nurse at Hacienda HealthCare facility, alleging he sexually assaulted and impregnated an incapacitated woman at the center.

The woman gave birth to a boy Dec. 29. Staff members told a 911 operator that they had not known she was pregnant.

"From the minute we first became aware of the crime, we have virtually worked nonstop seven days a week to resolve this case," Phoenix Police Chief Jeri Williams said in announcing the arrest Wednesday morning.

Williams joined Mayor Thelda Williams at Phoenix police headquarters for an update on the case Wednesday.

The nurse, Nathan Sutherland, is a licensed practical nurse who was primarily responsible for caring for the victim woman at the time of the assault, police said. He has worked at Hacienda since 2011.

He was booked into Maricopa County Jail on Wednesday. At an initial hearing, his attorney said there was "minimum" evidence his client committed the crime.

A court commissioner set bail at $500,000.

The parents of the patient who gave birth are aware of the arrest.

State records show Sutherland was licensed as a clinical nursing assistant in 2005 before he became a licensed practical nurse. Hacienda HealthCare officials say Sutherland went through an "extensive background check" when he was hired.

He was terminated "the moment our leadership team learned of his arrest," said a statement the facility released this morning.

"Every member of the Hacienda organization is troubled beyond words to think that a licensed practical nurse could be capable of seriously harming a patient," the statement said. "Once again, we offer an apology and send our deepest sympathies to the client and her family, to the community and to our agency partners at every level."

Officials with the nonprofit health care company say they will "continue to review and improve what is already an in-depth vetting process for caregivers at Hacienda."

The Phoenix police crime lab determined Tuesday that a DNA sample taken from Sutherland matched the baby's DNA. Sutherland was arrested the same day.

Police had announced they would be testing the DNA of all the facility's employees.

Phoenix Police Sgt. Tommy Thompson said police didn't have the opportunity to collect Sutherland's DNA through a court order until Tuesday.

Sutherland declined to answer investigators' questions after he was arrested Tuesday, Thompson said.

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Sutherland was booked into Maricopa County Jail on Wednesday, charged with one count of sexual assault and one count of vulnerable adult abuse. Maricopa County Superior Court records show Sutherland has not been charged with any other major crimes.

He appeared in Maricopa County Superior Court alongside Mesa attorney Dave Gregan for an initial appearance shortly before noon. He did not enter a plea.

Gregan asked the judge to set a low bail given the "minimum" evidence and the fact that Sutherland has lived in Arizona since 1993 and he doesn't have a criminal history. The defense plans to do its own DNA test.

"There's no direct evidence Mr. Sutherland committed these acts," Gregan said.

If Sutherland is released, he'll be placed on house arrest and will have to wear an electronic monitoring device. He won't be allowed to return to Hacienda or contact the victims as conditions of his release.

His next court appearance is scheduled for Jan. 30.

Thompson said police were still working to determine whether other patients inside the 60-bed facility were assaulted.

Thompson said the baby was full-term and has since been released from the hospital.

"We can't always choose how we come into this life, but we can choose as a community how we will love this child – and that's what we need to do," he said.

According to court records, the woman, who is a member of the San Carlos Apache Tribe, has been a patient at Hacienda for 26 years. The records say the woman is "not alert" and needs a "maximum level of care."

In the weeks since the 911 call calling for help after the child's birth, police and state agencies have launched investigations and the director of the facility resigned. Hacienda HealthCare also hired former Maricopa County Attorney Rick Romley to conduct an independent investigation into patient safety.

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