Police have been called in to investigate after a suspicious house fire in Queanbeyan on the weekend.

Fire crews were called to the fire at a home in Downey Street about 11.40pm on Saturday night, eventually extinguishing the fire, but not before an estimated $150,000 to $200,000 damage had been caused.

Crime scene examiners conducted a search of the site yesterday, which revealed the house had been ransacked prior to the fire starting.

The house was left largely destroyed, and authorities believe the home will now need to be demolished.

No one was at home at the time of the fire.

Investigators have urged anyone with information about unusual or suspicious activity in the area to come forward. People with information should call Crime Stoppers on 1800 333 000 or use the Crime Stoppers website.