People are being urged to be careful in Canterbury, as firefighters brace for yet more blazes

Crews are continuing to battle a 30-hectare vegetation fire alongside State Highway 1 near Burnham, Canterbury, that's forced the evacuation of some homes.

Preliminary findings have linked the fire to a vehicle tyre blow-out, but that won't be confirmed until the investigation's complete.

Incident Commander Dave Berry says the fire is not being treated as suspicious.