Update, 1.20pm: A child has been flown to the Royal Children's Hospital following an explosion in Mortlake.
A Country Fire Authority spokeswoman said the boy was in his father's shed when two products were accidentally mixed together which gave an oxidising effect, causing burns to his face and arm.
He was treated by paramedics at the scene and flown to hospital.
There were five CFA and three FRV trucks in attendance.
Crews remain on scene working to decontaminate the site, including a CFA scientific officer.
Earlier: A child has been flown to a Melbourne hospital following an explosion in Mortlake.
Paramedics were called to reports of an explosion just before 11am on Saturday to treat a preschool-aged boy who received burns to his face and arm.
An Ambulance Victoria spokeswoman said the young patient was flown to the Royal Children's Hospital in Melbourne in a stable condition.
Fire Rescue Victoria hazmat appliances attended the scene from Hamilton and Ballarat.
More to come.
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