A mechanical fault was behind a car fire at a mall in the Auckland suburb of Henderson today.

Explosion at a Henderson mall. Source: 1 NEWS

Scentre Group, which owns and operates Westfield in New Zealand, says at around 11.30am a car parked on the perimeter of the Westfield WestCity carpark caught fire, prompting the mall's evacuation.

The Fire Service was quickly on site to extinguish the fire. The group says it has been confirmed that it was caused by a mechanical fault.

Scentre Group says the centre was evacuated as a result of the smoke, and trade will resume as soon as it receives clearance from the Fire Service.

There are no reports of anyone being harmed. Fire communications said about 60 firefighters responded to the fire.

They are currently ventilating the area and searching the underground level and upper level of mall after toxic fumes seeped into the building.

NZTA earlier said the fire was causing "mayhem" on the roads near Catherine Street and warned motorists to use alternative routes.

#AklTraffic #Fireat Westfield Henderson is caused#Mayhemfor all roads in the area. Please avoid travel around Henderson. ^BM NZTA Akld & Nthlnd (@NZTAAkl) February 26, 2015

Witnesses told ONE News that it sounded like there had been an explosion in the area.

Police say the female driver of the vehicle was driving to the mall alone when she noticed smoke. However, it wasn't until she parked in the underground car park that she noticed the flames.