Sydney teenager found dead behind Ironbark Ridge Public School in Rouse Hill following alleged stabbing

A teenager has allegedly been stabbed to death behind schools in northwest Sydney.

Emergency services were called to a reserve on Caballo St at the rear of Ironbark Ridge Public School and Rouse Hill High School in Beaumont Hills about 4.20pm on Monday.

The 17-year-old boy suffered a fatal knife wound to his leg.

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Despite paramedics’ efforts, he was pronounced dead at the scene.

A 15-year-old boy was arrested after attending a police station in the city’s northwest about 7.30pm, accompanied by a parent.

“That (child) is under arrest and is assisting us with our inquiries,” Detective Superintendent Naomi Moore said.

Detectives remained on the scene on Monday evening, searching for weapons and possible suspects.

Paramedics treated the boy at the scene but he couldn’t be saved. Credit: 7NEWSDespite paramedics’ efforts, the boy was pronounced dead at the scene. Credit: 7NEWS

Moore said the dead teen had been with another boy when they were approached by up to three young males.

Police do not believe the meeting was random.

“I believe there is potentially some connection but … that’s going to take some time to draw out and as mentioned we are talking with someone who has handed themselves in to speak to us,” Moore said.

“Hopefully we’ll know some more shortly”.

A number of witnesses in the park at the time rendered first aid and emergency services were called.

“It would have been a horrifically confronting situation for those (witnesses) and I can only praise them for their efforts,” Moore said.

“It was potentially a dangerous situation they were walking into but they thought nothing of themselves to go in and render aid.”

Moore said the late teen was not linked to the local high school and it was too early to say if the incident was gang related.

“There is absolutely no indication about that. It’s very early in the investigation and that along with many other avenues will be part of that investigation but it is simply too early to say right now,” she said.

7NEWS understands two boys were seen running from the scene, one of them reportedly wearing a school uniform.

Police said they are still working to determine exactly how many other children attended, who they are and if they had any role in the deadly incident.

A crime scene has been established, and investigations are ongoing. Credit: 7NEWS

Attorney General Michelle Rowland said in a social media post that she was “deeply saddened to learn of the tragic loss of a young life”.

“My thoughts and deepest condolences are with the young boy’s family during this extremely difficult time,” she wrote.

“I know this news will be particularly distressing for local families.

“May he rest in peace.”