The fire erupted this morning - Friday, April 11 - and emergency crews say no one was injured in the incident.
A spokeswoman for Police Scotland said: "We can confirm that police were called to a report of a fire at a house in Old Luss Road, Helensburgh on Friday, April 11.
" No one was injured and the police investigation into this incident is ongoing.
"Anyone with information should contact Police Scotland on 101."
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