Firefighters were busy with a number of incidents overnight, including two more car fires.
The call-outs came after local crews responded to five car fires within a 24-hour period on Monday and Tuesday.
Fire crews were called to the first car fire on Kiewa Road, Nerrina, about 10.15pm.
Just 15 minutes later they were called to reports of a vehicle explosion on Stanley Street, Ballarat North.
Both are being treated as suspicious.
Crews also attended a grass fire in Barkly Street, Buninyong about 6.30pm before responding to a shed fire in Wendouree just before 9pm.
Contact Crime Stoppers on 1800 333 000 with any information relating to the car fires.
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