Two students from a Sydney private boys’ school are among three teenagers charged over the alleged sexual assault of a 17-year-old girl.

The boys, all aged 17, allegedly raped the girl at a home in NSW’s Macarthur region on Saturday.

St Gregory’s College has confirmed two of the teenagers attend the independent Catholic boys’ school in Campbelltown.

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It is not known whether the third boy charged is also a student at the school.

Police began investigating on Sunday after receiving a report of the alleged assault.

Following extensive inquiries, detectives executed search warrants at several homes across the Macarthur region about 7am on Wednesday.

The three boys were arrested and taken to Camden Police Station, while officers seized electronic devices and other items for further examination.

One teenager was charged with 11 offences, including six counts of aggravated sexual assault in company, three counts of sexual intercourse without consent, and one count each of sexually touching another person without consent and carrying out a sexual act with another without consent.

The second teenager was charged with eight offences, including six counts of aggravated sexual assault in company, as well as common assault and sexual intercourse without consent.

The third teenager was charged with two counts of aggravated sexual assault in company.

All three were refused bail and were due to appear before a children’s court on Thursday.

In a letter to parents, St Gregory’s College principal Matthew Brennan confirmed two of the school’s students were involved.

“I am very sorry to have to share the following news with our community,” Brennan said.

“As this is an ongoing criminal investigation and before the courts, it is important that we do and say nothing that could compromise those independent processes.

“We express our deep concern for the young woman police have said was the victim of the alleged sexual assault, and her family and loved ones.”

Brennan said sexual violence had no place at the college.

“It is abhorrent, what is alleged by police, and is the antithesis of what we stand for and the values that we embrace,” he said.

“These are very serious of allegations and the judicial process must now be allowed to take its course free of any commentary. 

“We ask everyone to avoid speculation or sharing of information that could impact the parties involved or the independent process now underway.”

St Gregory’s College is a Catholic day and boarding school for boys from Years 7 to 12.

According to its website, annual tuition fees are up to $12,350 for senior students, while boarding fees are $32,522 a year.