A suspicious house fire in Perth’s southern suburbs has destroyed two cars creating a damage bill of $200,000.

Arson squad detectives are investigating the fire that started yesterday afternoon at a home on Molloy Circle in Atwell.

Emergency services were called to the scene at about 3.15pm, where two vehicles were on fire in the carport.

The fire spread to the roof of the home, and both cars were completely destroyed.

The estimated damage bill is $200,000.

Anyone who saw any suspicious activity is urged to contact Crime Stoppers on 1800 333 000.

(Photo: WA Police.)