One person has been taken to North Shore Hospital after a car rolled on the Northern Motorway this afternoon.
Emergency services were called to the crash just north of the Onewa Road off-ramp at 1.09pm.
A St John spokesperson said one person was serious and has been transported to North Shore Hospital.
"Two others were in a minor condition."
New Zealand Transport Agency said all lanes were re-opened by 2.50pm but significant delays are still expected as congestion from the earlier crash clears.
Traffic remained very heavy in the area and police are continuing to urge motorists to avoid the area if possible.
North-bound traffic was being diverted off the motorway at Onewa Road and traffic is building up back across the Auckland Harbour Bridge.
Earlier this afternoon there was a tail queue at Newmarket as well as queues southbound near the accident due to rubberneckers, according to Newstalk ZB's Time Saver Traffic.
The Serious Crash Unit is attending the incident.
Update: All lanes on the Northern Motorway re-opened at 2.40pm, though drivers are advised by the NZTA to still expect delays.
- NZ Herald