Doonside Technology High School stabbing: One dead and another fighting for his life after brutal knife spree in Sydney's west

A teenage boy has been stabbed to death and another is in a serious condition after a knife attack near a school in Sydney's west on Friday.

The pair were attacked outside Doonside Technology High School on Power Street, in Doonside, near Blacktown, around 3.40pm.

They managed to stagger to the nearby police station nursing serious injuries where officers desperately tried to treat them on the spot. 

But one of the two teens died at the scene, while the other is now fighting for his life in hospital. A third person found nearby was later arrested by police.

A school coach with its hazard lights flashing was seen locked down at a bus stop in an area sealed off by police as the investigation continues.

'About 3.40pm, emergency services responded to the stabbings near a school on Power Street, Doonside,' said a police spokesman.

'Before officers attached to Blacktown Police Area Command could arrive on scene, two teenage boys presented to Blacktown Police Station with stab wounds.

'They were treated at the scene for serious stab injuries. A boy in his teens died at the scene and the other teenage boy was taken to hospital in a serious condition.

'Police have established crime scenes at both locations and are investigating the incident.

'Following inquiries police have arrested one person nearby.'

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