Fireball rocks apartment complex

Fire and smoke erupt from the roof of the apartments at Princes Wharf. Photo / Carsten Rauer

A large fireball erupted from the top of a building on Auckland's waterfront today, followed by billowing toxic smoke.

Fire safety officers are investigating the cause of the explosion which started in a cupboard on the second-storey carpark of the Princes Wharf block.

Auckland city senior station officer Chris Scott said there was quite a build-up of debris in the building's "ducting", or chimney.

More than 100 people shaded their eyes to watch as firefighters were hoisted into the multi-storey Euro Restaurant & Bar building by cranes, to dampen smouldering spots and ensure the building was safe.

This included Mangere siblings Carley and Cayde Hazleman, 6 and 8, who said they were "playing on a boat" in the Viaduct when they saw "lots of fire" and "lots of smoke".

Flatmates Lorena Ribriro and Paloma Albino, 21 and 24, were sleeping off New Years Eve hangovers when they were awoken by the fire alarm and evacuated. They were concerned about water damage to property by the sprinklers.