But he said it was too soon to announce the findings or to say if the fire was deliberately lit, as the investigation was still wrapping up.
A Fire and Emergency spokesperson said they have spoken with schools that were holding camps in the area.
Stackhouse said crews would continue to mop up hotspots on Tuesday, and will meet with landowners on Thursday.
Meanwhile, wind caused flare-ups at the site of a large vegetation fire in West Melton overnight, but firefighters were able to prevent flames breaching containment lines.
Incident Commander Dave Key said the flare-ups happened when wind fanned partially burned vegetation and trees into flame.
The fire, which began on Sunday night, has burned across more than 130ha.
Homes and a caravan park were briefly evacuated in the early hours of Sunday morning, but all were allowed home.
Crews were also at the nearby Kirwee fire, which has been burning since Saturday and is mostly contained.