UPDATE: A man has been arrested following three suspicious fires in Bendigo on Wednesday morning.
A Victoria Police spokeswoman said a 36-year-old man was arrested in the Bendgio CBD at about 12.45pm on Wednesday.
He has been assisting police with their inquiries.
EARLIER: COUNTRY Fire Authority crews have attended a third fire in the city on Wednesday morning.
A passerby who saw smoke coming from under a house in Wills Street in Bendigo alerted authorities just before lunchtime.
Bendigo Country Fire Authority station officer Morgan Mitchell said it was fortunate the person noticed the smoke.
"It could have been worse. It was lucky someone walking past was observant and picked it up," he said.
Firefighters quickly controlled the fire when they arrived on scene.
"It was a small fire, on arrival it was dealt with in about 30 seconds," Mr Mitchell said.
He said the fire started underneath the house and the flames were only inches high.
Police will investigate the cause of the fire.
A crime scene has been established in King Street in Bendigo after a unit fire started about 9.45am.
Before that, authorities attended a house fire in West Bendigo's Inglis Street.
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