A man who accidentally started a bushfire in Baldivis that burned through more than 1200 hectares and put several homes at risk on Thursday afternoon has publicly apologised for the incident.

In an interview with Nine News reporter Kamin Gock, James Hamling said he still felt sick about starting the blaze.

James was driving in the area when the wheel bearing of the boat he was towing collapsed, starting a fire. Nine News

"I was basically coming down the road and the wheel bearing collapsed and it started a small fire and with the winds I just couldn't put it out," he said.

"It just took off to the other side of the road, I rang up 000 and before I knew it it was out of control."

The fire was first reported at 12.02pm on Thursday near the intersection of Karnup Road and Young Road in Baldivis, but quickly spread to nearby areas, prompting the Department of Fire and Emergency Services to issue an emergency warning.

It has since been downgraded to a watch and act after 180 firefighters brought the blaze under control overnight, but strong winds are expected to continue throughout Friday, possibly causing the fire to break containment lines.

Aerial images of the fire ground on Friday afternoon. Nine News

People will not be allowed to return to the area until further notice and an evacuation centre has been set up at Mike Barnett Sports Complex, on the corner of Dixon Road and Goddard Street in Rockingham.

A number of roads have been closed including Folly Road and St Albans Road from Kwinana Freeway to Mundijong Road, Mundijong Road from Kwinana Freeway to Kargotich Road, Duckpond Road from Mundijong Road to Banksia Road, Young Road, Doghill Road and Horsfall Road.

Although WA's arson squad has formally ruled the blaze as an accident, Mr Hamling said he would like to thank all the crews involved and apologise to anyone affected by the fire.

"I sincerely apologise, I still feel sick about it now," he said.

"I know the arson squad said it's an accident, don't worry about it, but I still feel personally responsible so I just apologise and I'd just like to thank everyone involved."