A suspicious fire has destroyed a high school library in Perth causing $1 million worth of damage.
Firefighters were called to Atwell College about 2.45am on Monday with crews taking just over an hour to bring the blaze under control.
The Arson Squad are treating the fire as suspicious, with emergency services initially understanding it began in an air-conditioner, and a $50,000 reward is on offer for information that leads to the identification and conviction of an arsonist.
A Department of Education spokeswoman told AAP other buildings were not damaged and students returned to school as normal on Monday.
