A video was posted on a community-run Facebook on Wednesday night purporting to show one girl assaulting another at the north Canberra school.

The person who posted the video said she was the mother of the alleged assault victim and had decided to publicly release the footage because she had no confidence in the way the school was dealing with the incident and other instances of bullying against her daughter.

The video has since been removed. Police are investigating the incident.

Ms Berry said on Friday she had been briefed several times on last year's alleged assault.

"It is part of a police investigation so I can't really comment much more on the incident other than an incident did occur," she said.

"This morning I was able to catch up with the principal at Amaroo School and she's been talking with the school community and with the people involved.

"Nobody accepts any kind of violence in our community, particularly in our schools, and I'm confident that the Amaroo School community will do everything they can to make sure that it's a safe place for everybody."

An ACT Policing spokesman said police were informed of the assault in December last year.

"The investigation is ongoing and it would be inappropriate to comment further."

On Thursday, an Education Directorate spokesman said it was "disappointing" the incident had surfaced on social media.

"Behaviour that is disrespectful and harmful to others should not be tolerated in our community and is unacceptable in our schools," he said.

"It is also important to remember that students and families themselves play an important role in promoting respectful relationships and we encourage families to talk about and demonstrate expected behaviours at home as well as at school."