Work to counter radicalisation sped up

NSW Premier Mike Baird has ordered work on counter-radicalisation, including in the state's schools, to be accelerated in the wake of last week's deadly terror attack on the Parramatta police headquarters.

While police on Wednesday said they were yet to establish a motive behind the attack on Friday, Mr Baird said he was concerned about religious radicalisation in the state's schools.

A number of people arrested in dawn raids across western Sydney on Wednesday had attended Arthur Phillip High School, the same school as 15-year-old gunman Farhad Khalil Mohammad Jabar, who on Friday shot dead police accountant Curtis Cheng.

One of those arrested on Wednesday was a 16-year-old who was in the same year at Arthur Phillip High School as Jabar.

A 17-year-old arrested on Tuesday is also a student at the school.

Mr Baird on Wednesday said while there had been "some isolated incidents", he had asked the Education Department to accelerate programs aimed at countering radicalisation in schools.

"It's important we understand this," he told reporters.

"We have a position where the advice we have, not just there but every school across the state, we have close to a million students on a daily basis who go to our schools, (is) they are safe.

"In that context, there have been some isolated incidents."

Still, he said there was "no doubt" more could be done.

"Over the past few months, we have done a lot of work, a lot of work, in relation to how we are going to combat radicalisation," he said.

"There is a range of programs that we are looking to implement both in the Muslim community, in our schools, and together in the broader community. There is a role for all of us to play."

Arthur Phillip High School principal Lynne Goodwin has also moved to reassure parents, saying police had advised that there was no "ongoing threat".

"I would like to reassure the whole Arthur Phillip High School community that the school continues to be in close liaison with the Department of Education and the NSW Police to uphold our exemplary levels of student safety and student wellbeing," Ms Goodwin said.