Northern Grampians Crime Investigation Unit detectives are investigating a fire that was reported in Ararat's Alexandra Gardens on Sunday, May 9.
The fire was started on the north side of the gardens, near the fernery.
A Country Fire Authority spokesperson said the fire was quickly under control.
"The CFA was notified at 12.45pm about reports of a fire that was spreading to trees," they said.
"The incident was under control at 12.53pm. Two vehicles were on scene, both from Ararat Fire Brigade. Police were also required on scene."
There has already been one deliberately lit fire in Alexandra Gardens in 2021, as a fire was lit at Gardens Lake Cafe in February.
A Victoria Police spokesperson said in this instance minimal harm was caused.
"Emergency services attended the Girdlestone Street garden following reports of a small fire about 12.45pm," they said.
"The fire was quickly extinguished by fire authorities and caused minor damage to a fence."
The spokesperson asked people with information on the fire contact authorities.
"Police are treating the fire as suspicious and urge any witnesses to come forward," they said.
Anyone with information can contact Crime Stoppers on 1800 333 000 or submit a confidential crime report at www.crimestoppersvic.com.au.
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