The cause of an oil leak that sparked a fire along Auckland's waterfront this morning and attracted a large emergency response is being investigated.
Seven Fire Service appliances were called to the Tank Farm at Wynyard Quarter about 10.40am after an automated alarm was activated, said Fire Service spokesman JaronPhillips.
Mr Phillips said oil had leaked from a bitumen pipe line and caught fire in the bulk liquid storage facility, Marstel Terminals.
"It was extinguished but flared up, so we are standing by in case it flares up again," he said.
"It has the potential to [reignite] so that's why it attracts this response."
Specialist foam equipment was on site, Mr Phillips said.
Managing Director of Stolthaven Australiasia that owns the storage facility, Graham Catley, said the source of the leaked oil, that is heated so it can be circulated through pipes around the Marstel Terminals building, was being investigated.
"You can sometimes get a pinhole leak in a pipe and it drips, which it appears has happened here, and for some reason that has ignited and we have had a very, very small fire which we have extinguished with our own fire extinguishers."