Sydney school put into lockdown

A school in Sydney's west was put into lockdown after a student was allegedly attacked by an intruder.

Police and paramedics were called to The Hills Sports High School around 2.15pm on Wednesday following reports of the assault, prompting the lockdown.

A male student, 15, was taken to Westmead Hospital with a minor back injury.

A male teenager, who was not a student at the school, was taken to Blacktown police station for questioning.