A boy told police he escaped from a man who grabbed his arm while in the toilets of Mandama Primary School, about 2pm on Tuesday afternoon.
The boy said he punched the man and broke free before fleeing and alerting a teacher who called police.
The school was placed in lockdown as police searched the area but were unable to locate the man.
Police said he was last seen leaving the school grounds on foot towards Corang Avenue.
The man was described as being of Caucasian appearance, aged 20-30, tall, with a skinny build and dark stubble.
Police said he was wearing a black hoodie with the hood up and black sunglasses.
Anyone with any information is urged to contact Crime Stoppers on 1800 333 000 or submit a confidential crime report to crimestoppersvic.com.au
