AUGUSTA — A Riverview Psychiatric Center patient attacked a nurse with a chair at the state hospital in a fit of rage and left her hospitalized with serious injuries to her face and eye, authorities said.

Frank Stewart, 23, was arrested Saturday at the state mental health hospital and taken to Kennebec County Jail, where he was charged with aggravated assault.

The incident comes as the beleaguered state hospital is losing millions of dollars in federal funding amid growing criticism of safety and operations there.

According to an affidavit by Capitol Police Officer Joseph Morelli, Stewart attacked a registered nurse with a chair just before 5 p.m. Saturday. Stewart “was angry with the staff because he refused to give the staff an aluminum plate,” Morelli wrote.

The nurse, Nancy Austin, suffered “severe swelling and laceration on the left side of her face. Her eye is swollen, black and blue,” Morelli noted.

Morelli said it did not appear that Stewart was delusional or suffering from severe mental illness at the time of the attack.

John Martins, spokesman for the Department of Health and Human Services, said in a statement that he would not comment on the Riverview employee’s medical condition.

“Riverview Superintendent (Jay) Harper and other staff members have reviewed this unfortunate incident against current policy and practices,” Martins wrote. “It has been determined that no changes are needed.”

Chris Quint, executive director of Maine State Employees Association Local 1989 of the Service Employees International Union, which represents about 65 registered nurses at the hospital, said Monday that he had no comment on the reported incident. A phone number listed for Austin was not in service Monday.

Kennebec County District Attorney Maeghan Maloney said Austin remained hospitalized Monday as a result of the attack. Maloney also said the jail was filling out paperwork over the weekend seeking to have Stewart held in a newly opened intensive mental health treatment unit at the Maine State Prison while this case is pending.

The incident echoes an attack in March 2013 when patient Mark P. Murphy, angry because he was denied a visit to his family, attacked a pregnant mental health worker, beating her about the head and stabbing her hand with a pen. That Riverview worker, Jamie Hill-Spotswood, had told hospital officials a week prior to being attacked that she felt unsafe in the facility, according to a federal lawsuit she has filed against the state. Hill-Spotswood claims the state failed to protect her.

A number of staff injuries at the hospital are a result of patient attacks. After the attack by Murphy, the state brought in corrections officers to monitor specific patients, and a report that a stun gun was used on a patient brought in federal regulators, who revoked the hospital’s federal certification.

As a result of their survey report, the Centers for Medicare and Medicaid Services revoked the hospital’s certification last September, making it ineligible for federal funds that amount to about $20 million annually. The state Department of Health & Human Services is appealing that revocation, and the hospital is seeking recertification.

Stewart was sent to Riverview in March 2012 after being found not criminally responsible for two assaults on staff members that occurred while he was incarcerated at Long Creek Youth Development Center in South Portland.

He had been at the juvenile center since 2007 and prior to that was housed in a series of group homes beginning as early as age 5, according to records in Kennebec County Superior Court.

Stewart previously pleaded guilty to a July 2009 sexual assault of a 5-year-old boy at Crescent Beach State Park in Cape Elizabeth that occurred while Stewart was there on a group outing with others from Long Creek. Stewart, who was a few weeks shy of his 18th birthday, was treated as an adult in that offense and sentenced to remain at the facility until he was 21 and register as a lifetime sex offender. He was also to be placed on 12 years of probation following his release on the sex offense charge.

Stewart’s actions halted group trips from both Long Creek and Mountain View, the youth center in Charleston, Maine, until policy changes were made.

Stewart made an initial appearance on the new aggravated assault charge in Kennebec County Superior Court on Monday accompanied by defense attorney Andrews Campbell. Stewart did not enter a plea, but was advised by Justice Daniel Billings of the charge.

After hearing from the prosecutor, Assistant District Attorney Joelle Pratt, Billings set bail at $15,000 cash with conditions that ban Stewart from contact with Austin and from possession of dangerous weapons.

Stewart asked the judge what would happen with his care, noting that he now cannot see Austin and “she’s my nurse.”

Billings said Stewart’s doctors would be dealing with his care.

Stewart said he was at Riverview after being found not criminally responsible for attacks on three corrections officers. Stewart also told a judge that the record of the sex conviction against him should be sealed.

Billings assigned defense attorney J. Mitchell Flick to represent Stewart since Flick already represents him when Stewart seeks changes in the conditions under which he’s held at Riverview, such as time off hospital grounds.

Stewart is scheduled for another court hearing Oct. 14.