DURHAM, N.C. (AP) — Lawsuits against Duke University allege that counselors at a camp for chronically ill children negligently left campers unattended while one child coerced others into sex acts — allegations that Duke denies.

The lawsuits were filed by guardians of two children who say they were abused by another camper at Camp Kaleidoscope, and one child who says he was psychologically harmed by seeing the acts. They were filed in 2017 and 2019 and were first reported Tuesday by Indy Week .

Lawyers for Duke University denied in court papers that the camp counselors failed to supervise the children, or that the staff behaved negligently.

“All defendants involved with this camp exercised reasonable care and diligence in their respective roles at the camp,” the lawyers wrote in 2017.

University spokesman Michael Schoenfeld declined to comment on the lawsuit Wednesday, citing respect for the privacy of the children and families involved.

Duke doctors, faculty and employees operated the sleep-away summer camp from 1979 to 2017 to serve children with chronic medical conditions, offering activities including swimming, games and crafts at a lake north of Durham.

The lawsuits allege the sex acts happened in 2017 in a cabin housing five boys between the ages 7 and 10, on nights when adults left them unsupervised for an hour or more while attending meetings. One night, a counselor returned to the cabin to find several of the boys engaged in oral sex, the plaintiffs write.

In court filings, Duke lawyers denied those allegations.

The lawsuits don’t accuse any adults of participating in the sex acts.

The three lawsuits allege that one of the bunkmates had a pre-existing case of HIV/AIDS, creating a risk of exposure. The most recent lawsuit, filed last Friday, alleges another bunkmate had a pre-existing case of oral herpes. One of the plaintiffs is undergoing precautionary HIV treatment, according to one of the lawsuits filed in 2017, which doesn’t make clear if he is believed to have contracted the disease.

The lawsuits allege that the sex acts were instigated by an 8-year-old camper who wasn’t sick but attended because his father worked for Duke.

Guardians of two of the boys say camp officials called to tell them what happened and to disclose possible HIV exposure. Duke lawyers argue that the phone calls were mischaracterized by the plaintiffs.

The third lawsuit, filed this year, claims the university never notified the parents of the boy who saw what happened but didn’t participate.

The plaintiffs say the camp wasn’t held last year.

Camp directors wrote a message to staff on July 20, 2017, which was sent to parents, saying that the camp was closing “following an encounter among several campers last week that required us to take a close look at our operations,” according to court documents. The message also asked parents to “refrain from posting any information about the Camp on social media or in communication to parents.”