Motorists heading into Auckland are warned to expect long delays on the Southwestern Motorway after a multi-car crash this morning.

The crash on State Highway 20 at the Puhinui Rd overbridge was earlier blocking the right northbound lane but had now been pushed clear of the traffic, the NZ Transport Agency says.

Despite the crash being cleared, traffic was still heavy approaching Hillsborough Rd.

"Avoid this route if possible or expect long delays," the agency tweeted.

SH16 NORTHWESTERN MWY - CRASH - 7:10AM
A crash is blocking the right lane citybound after St Lukes Rd. Pass with care & expect delays this morning. ^TP pic.twitter.com/32U9dO1ady

— NZTA Akld & Nthlnd (@NZTAAkl) November 12, 2018

Citybound traffic on the Northwestern Motorway is also being delayed by a crash blocking the right lane of the Northwestern Motorway just after the St Lukes on ramp.

The NZTA said traffic was heavy between Hobsonville and Royal Rds as a result.

Citybound traffic is also heavy on the Southern Motorway between Drury and Takanini and moderate to heavy through Te Irirangi Dr and between Princes St and Mt Wellington.

The Northern is heavy between Oteha Valley and Onewa Rds.

Elsewhere, four people have been taken to hospital after an early morning crash east of Auckland, near Beachlands.

The two car crash took place on the Whitford-Maraetai Rd, just after Okaoro Dr at about 5.15am, a police spokeswoman said.

The crash initially blocked the road as the four people were taken to Middlemore Hospital for a range of minor to moderate injuries and the damaged cars were towed from the scene.

By 6.30am, Auckland Council had been called with a request to clean up oil from the road, but traffic was able to pass through on one lane.