Police are calling for information on a house fire at Risdon Vale this morning which is believed to have been deliberately lit.

Fire crews were called to the vacant building on Poplar Road about 1.50am on Monday.

Much of the interior of the house was impacted by fire and smoke damage.

A witness reported seeing two people near the property around the time of the fire and running towards Sycamore Road.

Anyone who may have seen someone acting suspiciously in the Poplar Road area, or who may have CCTV or dash-cam footage around the time the fire started, is asked to contact police on 131 444.

You can also report anonymously to Crime Stoppers at 1800 333 000 or online at www.crimestopperstas.com.au