Some victims of the strong-arm police tactics were seen having their faces dowsed in milk and water in attempts to ease their pain.

The disturbance took place as around 40 students protesting against education reforms attempted to enter the Sydney Masonic Centre, where federal education minister Christopher Pyne was giving a speech.

ABC footage shows the students chanting “No cuts, no fees, no corporate universities” as they march down a foyer. One police officer can be seen pursuing them down the corridor before flinging at least one student to the ground as he takes up position at the main door and prevents the demonstrators from entering.

Other officers attempt to push the students back, but the first policeman – still guarding the doors – suddenly begins to pepper-spray the frightened students for several seconds. At once point he appears to be holding student Ridah Hassan in position with his left hand before using his right to spray her in the face from close range.

The students, several screaming or overcome by the spray, were then forcefully escorted from the building as police formed a barrier across the entrance. Many continued to chant: “This is not a police state, we have the right to demonstrate.”

Ridah, from the National Union of Students, told ABC: “The students tried to enter the building and we were, like, pushed by the police and I was pepper-sprayed right in the face. My face is on fire.”

New South Wales Police have launched an investigation into the incident. Meanwhile a national protest against the reforms is planned for March 25.