'Slowly dying': Boxing Day shoppers lose their minds over Sylvia Park chaos

Boxing Day shoppers are losing their minds as traffic woes and parking problems lead to outbursts of anger online.

Despite being known as one of the busiest days of the year, hordes of eager Kiwis have ventured to Sylvia Park, New Zealand's biggest mall. And instead of finding a bargain, they've discovered heavy traffic and a lack of parking.

"From the motorway off-ramp, all the way to the car park - Boxing Day shopping at Sylvia Park has been mayhem," one person posted to Twitter.

"Currently slowly dying in Sylvia Park. Do not recommend," another said.

People were already queuing before the mall opened, while over 35,000 people were inside by lunchtime. Images show the crush of shoppers filling entire hallways.

The New Zealand Transport Authority warns vehicles are backed up on the motorway leading to the mall and people need to "avoid the area".

"Traffic continues to be heavy in both directions through the Mt Wellington interchange with queues at both the northbound and southbound off-ramps," it posted to Twitter.

"Avoid the area and continue to expect delays."

A spokeswoman for Sylvia Park told NZME traffic management was on site and people need to be "patient" and "kind".

"In some instances we've just shut down some land so we can let people out," they said.