However, an ambulance called to the crash was sideswiped by a vehicle, which was last seen heading down Oaks Rd, off SH1.
4.55pm:
- Traffic remains busy in Auckland. There's heavy congestion on the Southern Motorway southbound between Newmarket and Takanini, and northbound between Princes St and Khyber Pass Rd and again between the city and Victoria Tunnel.
- The Southwestern Motorway is heavy in both directions between Onehunga and Manukau.
- West-bound traffic is busy on the Northwestern Motorway between Waterview and Lincoln Rd.
- There are also patches of heavy traffic in the northbound lanes on the Northern Motorway, including between Onewa and Northcote roads, Tristram Ave and Constellation Dr, and again around Redvale.
4.20pm:
- A crash is blocking lanes between Oakleigh and Otaika, south of Whangarei, causing delays in both directions, the NZ Transport Agency tweeted.
Emergency services are on the way and it's understood up to three vehicles are involved.
- In Wellington, northbound traffic is still congested between Peka Peka and Ōtaki, with queues back to Waikanae.
4pm:
- SH1 Northern Motorway northbound: Slow before the Johnstones Hill tunnels and Wellsford, and heavy at Warkworth
- SH1 Southern Motorway southbound: Slow to Takanini
However, good news for motorists held up by a breakdown on SH1 northbound at Greenlane, where a broken-down bus caused delays this afternoon.
This has now been cleared.
Motorists were earlier warned to expect delays leaving Auckland.
Traffic maps show congestion at Puhinui through to Takanini and chokepoints at motorway on-ramps at Manukau.
At 3pm, NZTA tweeted that a bus breakdown was blocking the left lane on the Southern Motorway citybound beside the Greenlane on-ramp.
"Pass with care and expect delays through the area."
Auckland Transport is predicting delays northbound and southbound on SH1 this afternoon.
Wellingtonians fleeing the capital for the long weekend are facing congestion between Peka Peka and Otaki.
READ MORE:
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Some roads in the Auckland CBD have reopened as the convention centre fire is controlled and moved into the "recovery" phase, but motorists are still advised to expect delays or avoid the area.
The far left lane on Nelson St - heading from the Northwestern Motorway - is open, and Federal St is now fully open.
Some bus routes are still taking a detour around the cordoned-off site.
Christchurch Police and traffic control are responding to a crash involving a truck and two cars in Rolleston.
Police were advised of the crash at the intersection Dunns Crossing Road and Walkers Road, through which SH 1 runs, at around 6pm this evening.
A police spokeswoman said there was nothing to suggest diversions are required there at the moment.
Police are reminding motorists to wear seatbelts, drive sober and to the conditions, and that the tolerance level for speeding is 4km/h from 4pm Friday to 6am Tuesday.
Last year, there were five motor fatalities over Labour weekend - two drivers, two passengers and one motorcyclist, down from six in 2017.
There were 130 reported injury crashes during the long weekend last year, more than half occurred on urban roads.
