A witness believes at least a dozen cars have been destroyed in the blaze.A witness believes at least a dozen cars have been destroyed in the blaze.

Smoke can be seen over Whangārei Hospital. Photo / NZMESmoke can be seen over Whangārei Hospital. Photo / NZME

Emergency services at Whangārei Hospital where a fire ignited in a carpark. Photo / Brodie StoneEmergency services at Whangārei Hospital where a fire ignited in a carpark. Photo / Brodie Stone