CFA brigades were called to Lilydale Marketplace on Tuesday 19 July to what originally came through as a building fire on Hutchinson Street.
The shopping centre’s smoke detectors were activated around 8.30am and crews responded to the alarms.
Posting to social media, Lilydale CFA noted that on arrival “it was established that a 4.5kg Dry Powder extinguisher had been maliciously activated in the corridor near Big W, causing powder to spread over the length of the passageway.”
Coldstream CFA volunteers were also on site to help, setting up a ventilation fan to clear the powder from the air through the corridor out an external door and away from the centre.
“Police were notified and are investigating with Centre Management,” the post said.