Young students at Sydney's Macquarie Fields Public School were in class when a bullet smashed though a window today, with NSW Police calling the shooting a totally "reckless" act.
A teacher called officers to the school on Fields Road at about 12:45pm, reporting a metal projectile had broken a classroom window.
The children inside the classroom were in year 1 and year 2.
The school was not placed into lockdown, and no students or staff were injured during the incident.
It is understood the small bullet remained intact, indicating it was likely shot from a long distance, and was not fired in a targeted attack.
Detective Superintendent Grant Healey said there was not "much force" behind the lightweight projectile.
"Early investigations show it wasn't targeted," he said.
"For the little kids at the time, they just heard a smashed window.
"The bullet has come into the classroom, but it's been stopped by the blind, so it hasn't come into the classroom with any speed or velocity, just enough to smash the window.
"It's a totally reckless act by somebody who is acting in a way with a firearm that is very dangerous for the community."
The police officer said he was still waiting for details from a ballistics report, but urged anyone with more information to come forward.