An attempted molotov cocktail was found burning in the staff car park at Grey Main School, in Greymouth last night.
A parent living nearby discovered the small fire in a plastic soft drink bottle with a rag stuffed in the neck, when he wandered over to the school to pick up his child's scooter, about 8pm.
Associate principal Terry Drake said no buildings were threatened and the incident was announced at school assembly this morning.
"It was a very small fire and police told us that no accelerant had been used."
Security at the school has been stepped up and police said they would patrol the area more often.
The parent doused the fire himself before contacting the police. A dog and handler were immediately dispatched but they lost the scent neaby.
Police are treating the fire as arson and are having the remains of the bottle forensically examined.
They also want to hear from anyone who may have seen suspicious activity in the vicinity of the school last night.
- The Greymouth Star