Firefighters have contained a blaze that was threatening lives and homes in West Australia’s south.

An emergency warning was issued for the northern part of Gelorup, south of Bunbury, on Thursday morning.

By early afternoon, the alert level had been downgraded to an advice as the bushfire had been contained but not controlled, leaving firefighters strengthening containment lines.

The Department of Fire and Emergency Services said 80 hectares had been burnt.