Fairy Meadow resident Michelle Waples lost her Toyota C-HR Koba to the blaze that broke out below her apartment complex on Sunday.

Mrs Waples said they saw people going downstairs, then heard bangs.

She was "absolutely gutted" to discover her year-old vehicle was among the five destroyed in the fire.

"I love my car, everyone who knows me knows how much I love my car," Mrs Waples said.

Fire and Rescue NSW Illawarra duty commander Inspector Jeremy Hood said the cause of the fire - and whether it was suspicious - had not been determined.

Inspector Hood said crews conducted atmospheric monitoring in the apartment building before letting residents return to their homes.

Wiring was damaged in the fire, he said, but the building was structurally sound.

Earlier

Vehicles were found ablaze underneath a Fairy Meadow apartment complex on Sunday afternoon, forcing the evacuation of residents.

Up to six Fire and Rescue NSW crews were called to the scene of the fire on the Princes Highway, at the bottom of Mount Ousley Road, where three to four vehicles were found alight.

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Smoke plumes could be seen filling the sky.

The call came through to emergency services about 2.30pm, with the fire able to be contained within around 35 minutes.

Police and Endeavour Energy were also called to the scene.

It's understood four cars and a motorcycle have been destroyed in the fire, while around 60 people were forced to evacuate residences.

MORE TO COME

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