The WA Police Arson Squad are investigating a suspicious fire at a Cooper Street property on Friday that a handful of homeless and vulnerable people had been living in for eight months.
Emergency services personnel and police rushed to the house fire on the corner of Sutton Street and Cooper Street about 9.20am on Friday morning.
A handful of people were asleep in the property at the time, but no one was injured in the blaze.
A Department of Fire and Emergency spokeswoman said $50,000 worth of damage was caused by the fire.
An occupant of the home, Dave Sansoni, told the Mandurah Mail he believed he had been "targeted".
Rewards of up to $50,000 are available for information that leads to the apprehension and subsequent conviction of an arsonist.Police Media spokeswoman
"I was cleaning the home up for the owner and I was given it cheaply to rent," he said.
"Other people are staying here."
Mr Sansoni said he had been living in the property for about eight months.
A Department of Emergency Services spokesman confirmed the fire was being deemed as suspicious, with police to conduct further investigations.
She said the fire was contained to the front room of the property, which was a "very positive outcome".
Two units from Mandurah Volunteer Fire and Rescue service, two units from Mandurah Fire and Rescue service, Falcon Volunteer Fire and Rescue Service, Rockingham Fire and Rescue Service and the fire investigations team attended the blaze.
Two neighbours, who both wished to remain anonymous, said they believed it was a squat house for homeless and transient people.
"It is a drug house and a squat house," one neighbour said.
"You see people coming and going all the time."
A WA Police spokeswoman said police were investigating the circumstances surrounding the cause of the fire.
"Police would like to speak to any person who has any information relating to this fire," she said.
"Rewards of up to $50,000 are available for information that leads to the apprehension and subsequent conviction of an arsonist.
"Anyone with information is urged to call Crime Stoppers on 1800 333 000 or report online atwww.crimestopperswa.com.au.
"Callers may remain anonymous if they wish."