WorkSafe is urgently making enquiries after high winds toppled containers in South Auckland overnight.
Forty empty containers fell like dominoes from their stacks at the Wiri freight hub, after winds reached more than 100 kilometres per hour.
Strong winds also brought down trees onto vehicles and across roads, brought powerlines down and travel was disrupted across the region.
The Auckland Harbour Bridge also saw speed restrictions in place and commuters were warned to expect delays.
Ports of Auckland confirmed to 1 NEWS they closed their sites between 2.30am and 3am, with its marine team having to rescue a runaway yacht in the early hours of the morning.
The vessel had been pushed up onto the rocks on the face of Bledisloe Wharf before making its way across Fergusson Basin and out with the tide, Ports of Auckland spokesperson Matt Ball said.
"They managed to keep it inside the dolphin with the tug as pictured until the pilot boat could get to it and put it alongside the old pilot boat pontoon."
Today's incident at the South Auckland storage yard comes after Janesh Prasad died at work when a tornado swept through the Wiri site in June.
The 41-year-old was a forklift mechanic working at the Ports of Auckland freight hub in Wiri when the twister hit.
The Ports of Auckland today told 1 NEWS his death was at the Conlinxx operation. Today's fallen containers are at the Containerco operation, which is next to it.
The company's managing director, Ken Harris, said because all Port facilities had been closed due to weather, no staff were onsite at the time.
Containerco told 1 NEWS they have imported specialist weather prediction equipment to be tested in Auckland along with liaising with MetService about future high wind predictions.
"Wind events strong enough to cause container stacks to fail are rare, however we have seen this site in Auckland affected twice in two-and-a-half months," Harris told 1 NEWS.
He said the facility is used to store containers no longer needed by importers so they can be upgraded and reused by exporters to send elsewhere.
Their site closes down once winds exceed 25 knots, which is still "greatly below the wind speed needed to move a shipping container".
Stack heights aren't usually a factor in causing them to topple, according to Harris, with a "very large dense stack" deemed more wind resistant than a smaller stack.
WorkSafe has confirmed to 1 NEWS it's making urgent enquiries into the operations of Containerco, Conlinxx and the Ports of Auckland.
A spokesperson said Conlinxx had taken pre-emptive measures following the incident in June, to reduce the size of container stacks.
WorkSafe was happy with its steps to ensure safety.
Pala'amo "Amo" Kalati was crushed to death by a container at the Ports of Auckland's Fergusson Container Terminal on August 30 last year.