A person has died in a crash in Wellington's Tawa overnight.
The two-car collision happened on State Highway 1 about 3:20am, a police statement said on Thursday morning.
"Diversions are in place however motorists should expect delays," the statement said.
The NZ Transport Agency/Waka Kotahi (NZTA) said SH1 northbound remains closed and is urging motorists to delay journeys or follow directions from emergency services.
"Delays are significant and heavy congestion is expected to remain throughout peak traffic hours this morning due to southbound traffic being down to one lane," a NZTA spokeswoman said.
"For those people travelling on the road this morning, please be patient and follow instructions from contractors and police onsite."
Footage from a Newshub reporter travelling along SH1 on Thursday morning shows traffic backed up and at a standstill.
Police said the serious crash unit is at the scene and an investigation is underway.
