Police and fire crews were called out to reports of two separate structure fires in the northern suburbs overnight.

The first report came in around 9:00pm last night when the occupant of the property returned home to find smoke coming from the location. Police and fire crews were advised and immediately attended the Nightcliff residence. There was extensive damage however fire crews ensured the blaze did not engulf the entire building.

A second report was made from an address in Alawa around 9:20pm. The house was fully engulfed by flames when police and fire crews arrived. All neighbouring occupants were evacuated as a precaution. It took multiple fire crews to extinguish the blaze which caused significant damage to the property.

There were no injuries sustained in either incident.

The two fires do not appear to be related.

Investigations are continuing.

Police are calling for any potential witnesses to come forward. Anyone with information is asked to notify police on 131444 or Crime Stoppers on 1800 333 000.