A security guard has been posted at a Sydney primary school after a man broke into the grounds and molested a number of pupils.
The "highly-visible" officer had been hired to perform foot patrols at Haberfield Public School, the NSW Education Department said.
Children were changing classes at the inner west school about 10.20am (local time) on Friday when a man entered the grounds.
Police say he sexually assaulted one girl, indecently assaulted two others and physically assaulted a fourth.
He has not been caught.
An education department spokeswoman said safety and security officers would visit the site today to assess security and provide advice.
The department was also meeting with parents, she said in a statement.
Counselling would be made available to kids and staff, the spokeswoman added.
NSW Teachers Federation president Maurie Mulheron says he hopes the attacks will prompt the state government to look at whether security is adequate across the school system.
"Whenever there's an incident like this it ought to remind us that we need to constantly review and evaluate what we do," he told AAP.
"A review might be able to see where we need to upgrade security."
Mr Mulheron said on the whole NSW schools were safe, noting that the incident was isolated and "very rare".
