It appears a cat may have caused a fire in a granny flat at Saratoga.

Firefighters were quick to arrive at the Mimosa Street property and extinguished the fire, which caused substantial damage.

Of most concern was a bottle of nitrous oxide which was inside the flat.

It had to be cooled down, amid fears it would explode.

Initial investigations have revealed the fire was sparked by a heater, knocked over by a cat while the occupant was out.