A BUSHFIRE in Nowergup got into peat soil and started burning underground, which meant firefighters were expected to still be monitoring the area some days after the all clear was given.
The Department of Fire and Emergency Services (DFES) said firefighters had worked to stop the bushfire from getting into bush adjacent to Neerabup Lake.
In an alert on Thursday, February 15 DFES said bushfire which had been burning near Wanneroo Rd and Wattle Ave West had been extinguished.
But firefighters would continue mopping up and patrolling the area for the next couple of days.
The fire, reported at 3.54am Sunday, 11 February is suspicious so people are asked to report any suspicious behaviour to Police Crime Stoppers on 1800 333 000.
The City of Wanneroo, managed the bushfire, which burnt 1ha of land.