A staff member at a state-licensed treatment facility for troubled teenage girls in Minnetonka flirted with a 14-year-old resident before raping the emotionally vulnerable teen, investigators revealed Tuesday.

The attack occurred on Dec. 22 at Nexus Glen Lake, a locked mental health facility located about a mile west of Interstate 494 and County Road 62, according to the state Department of Human Services (DHS).

The molestation and anal rape occurred in the resident’s bedroom, the DHS’s maltreatment report cited the teen as reporting to three Glen Lake employees.

The teen has a history of being sexually, physically and emotionally abused, and has suffered from depression and anxiety, the state investigators noted in their report.

The staffer denied the allegations and said the teen would make “playful” sexual comments to him, the DHS report read.

A sexual assault exam and the DNA evidence collected neither confirmed nor discounted that the assault occurred, the DHS report read. The staffer, who identity was not disclosed by DHS, no longer works at the facility.

The Hennepin County Sheriff’s Office has responsibility for any criminal investigation. A spokesman for the county attorney said he sees no evidence that a case was submitted by the Sheriff’s Office for consideration of charges. A Sheriff’s Office spokesman had no information to share about the case, including whether there was an investigation.

While investigators placed the blame for the assault solely on the staff member, the DHS found in a follow-up investigation that Glen Lake committed background check violations involving other two employees and fined the facility $400.

According to the DHS’s findings, the staffer had a habit of saying he “liked” the teen and would slap her buttocks.

On the day of the assault, the two spent much of the staffer’s shift “interacting with one another,” according the DHS review of the facility’s surveillance video. The two were spotted together in a supply room with the lights off and were smiling after exiting. Later in the kitchen, the girl pressed her body against the staff member, without him appearing to object. The rape occurred less than an hour later.

Although the staff member “denied the allegations, given the consistent information provided by the [resident] and that video surveillance corroberated parts of [her] statement, it was determined that the [resident’s] statements were more credible” than the staffer’s,” the DHS report’s conclusion read. “Therefore, there was a preponderance ... of evidence that the [staff member] has sexual contact with [the teen] at the facility.”

The 12-bed Glen Lake facility serves girls ages 14 to 19 with severe emotional and behavioral problems and is operated by the Plymouth-based nonprofit Nexus, one of the largest child residential treatment and foster care providers in the state.

The nonprofit has similar facilities in Minnesota in Onamia and Austin, two in Illinois and one in Baltimore. Nexus also provides foster care, adoption and in-home counseling services in Minnesota for children from birth to age 18.

In a statement read to the Star Tribune by one of its executives, Nexus said that as soon as staff became aware of the incident, “the employee was removed from the area immediately and had no further contact with the alleged victim. The employee was terminated.”

The girl was taken to a hospital emergency room, where staff there contacted law enforcement, the statement continued.

The state investigation found that a background check was done on this employee and that it “found no fault with Nexus” in connection with this incident, according to the statement.

DHS records online show one other investigation of Glen Lake by the agency since 2010. That involved involved two allegations of physical abuse. Both claims were unsubstantiated.