Harbour Bridge northbound lanes reopened

The scene of a serious crash on Auckland's Harbour Bridge has been cleared and the northbound lanes reopened.

Three motorcyclists were taken to hospital after a serious crash that caused traffic to be backed up on the motorway for 20 kilometres.

Police said three motorcyclists were injured in the crash, two were critically hurt and one seriously injured.

The motorcycle involved in the incident. Photo / Victoria Young

Police said the queue for motorists travelling north on State Highway 1 had backed up to Highbrook Drive and "grid-locked".

Three lanes were closed while emergency services attended the scene, with just one lane northbound open.

All lanes have now been opened.

Inspector Chris Robinson said the crash happened near the base of the southern side of the Harbour Bridge in a northbound lane about 12pm.

"If people are looking to head over the bridge today they're better off taking another route or not going at all," he said.

He said the motorcyclists appeared to be wearing gang patches. The Head Hunters gang was holding a Poker Run today in Silverdale, Auckland.

New Zealand Transport Agency (NZTA) recommended motorists take State Highway 16 and State Highway 18 to travel north today.

Traffic build-up following the incident on the Harbour Bridge. Photo / Jason Dorday

NZTA said northbound traffic queues on State Highway 1 had extended back to Gillies Avenue in Newmarket, and there was also queuing on the citybound lanes on the Northwestern Motorway.

The Curran Street on-ramp has been closed.

NZTA intended on using its lane barrier machine to provide an extra northbound lane over the bridge, but access to the machine has been affected by congestion in the area.

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