TWO youths were seen running from what was once part of Caringbah High School moments before a building was engulfed in flames and smoke on Tuesday afternoon.
Miranda police Detective Inspector Shane Woolbank said investigators believed someone deliberately lit the fire, which completely gutted an old auditorium.
He said a witness told police they saw two boys running from the site shortly before smoke started seeping out of the derelict building.
They were not wearing school uniforms and no further description was given.
Fire and Rescue NSW received a triple-0 call at 3.23pm. The first of seven fire crews was on the scene five minutes later and police closed Willarong Road between the Kingsway and Captain Cook Drive.
Firefighters from Miranda, Sutherland, Menai, Cronulla, Hurstville and Glebe fought the blaze, which was brought under control by about 4.40pm.
The adjoining Caringbah Bowling Club was evacuated as a precaution. No one was injured.
An excavator was brought in to knock down a remaining wall, which posed a safety threat, after the fire was put out.
Detective Inspector Woolbank said it was almost impossible to find out how the fire started at this stage as the building was completely destroyed.
A section of the former school ground where the fire broke was declared surplus land and sold in 2011. It has been rezoned for medium-density housing.
Police are appealing for information. Crime Stoppers:1800333000.
As it happened on Tuesday:
FIREFIGHTERS are battling a blaze at the former Caringbah High School site at Caringbah.
Fire & Rescue NSW Superintendent Ian Krimmer said firefighters were called to reports of a fire burning in the building about 3.20pm.
He said the old school auditorium has been completely gutted by fire.
Witnesses at the scene said about half a dozen fire trucks were on the scene and have contained the blaze.
The site, which had been sold for redevelopment, was zoned for medium-density housing.
See a You Tube video above by Amber Seggie.
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