A teenager has been taken into custody over a fire that damaged part of Comet Bay College in Secret Harbour.
Fire crews were called to the high school on Allatoona Avenue around 7.25pm on Thursday to find a two-storey building fully engulfed.
It took them nearly two hours to bring the blaze under control.
The school has confirmed several classrooms have been damaged.
No one was injured but a 15-year-old boy has been taken into custody.
Parents have been advised the school is closed today.
The fire scene remains under police guard.
Arson Squad detectives will be returning to the scene this morning to investigate the cause of the fire.
Anyone with information regarding this incident is asked to call Crime Stoppers on 1800 333 000 or report the information online at www.crimestopperswa.com.au.
Rewards of up to $25,000 are available for information that leads to the identification and conviction of an arsonist.
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