Last month, principal Kerry Morris issued a letter to parents and guardians informing them an assistant principal had begun investigating the incident a fortnight earlier.

In the letter, Ms Morris said the investigation centred on five year 8 students, who had subsequently undergone "disciplinary action" after an incident on May 12.

Parents of one student withdrew their child from the school, she said, while the parents of another had indicated their intention to do so. Suspensions for the remaining three students were "dependent on their actions or involvement", the letter said.

The letter said the disciplinary process had included "police interviews" and "education provided by the Dubbo Base Hospital Drug and Alcohol Unit". It said students involved had lost "college representative status", which would have to be earned back.

At the time of writing the letter dated May 27, parent interviews and "student re-entry" interviews were still taking place, according to Ms Morris.

The letter also asked parents not to approach staff members for comment on the matter.

Executive director of schools in the Bathurst Diocese Jenny Allen told the Daily Liberal she could not provide further details about the disciplinary process, including whether the suspensions had taken place.

"Any parent would want the privacy of their child respected," she said.

She said the school had issued the letter to "provide clarity" about various things they may have been hearing, and to "reassure people the school had acted in consultation with parents to resolve the issue".

Mrs Allen said the school had a counselling team that did "excellent work" and who had subsequently worked with affected students.

Asked if there had been any subsequent incidents of a similar nature, Mrs Allen said there had not.

A spokesperson for Orana Local Area Command said the children involved had "a very small amount of cannabis in their possession".

He said one child brought "a fingernail-sized clump" of cannabis to school and told other students "he could get more and sell it to them" if they wanted it.

"The police were involved some time after the commencement of the investigation by the school," the police spokesperson said.

"As a result no cannabis was seized or found in the possession of any person."

There was nothing to suggest a "drug ring" had been operating at the school, the police spokesperson said, and it appeared to be a "one-off incident".

He said police had also been asked to talk to students about the dangers of drugs.