Commuter chaos has hit the centre of the city with all northbound lanes on the Sydney Harbour Bridge closed because of an accident.

Two of the five southbound lanes are also closed after a multi-vehicle crash on Wednesday morning.

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Transport Management Centre has advised motorists to avoid the area.

Northbound motorists should consider delaying their journey or use Ryde Bridge as an alternative.

Southbound motorists should consider using the Sydney Harbour Tunnel as an alternative.

Major delays southbound on the Sydney Harbour bridge. 2 of 5 lanes closed. All northbound lanes shut from accident pic.twitter.com/eeEl1kmrWw

— Laura Tunstall (@LauraTunstall9) February 24, 2015

Anzac Bridge traffic actually moving. Drummoyne by far the worst of Vic Rd. pic.twitter.com/3V8hO3Ta8b

— Kathryn Wicks (@KathrynWicksSMH) February 24, 2015

. #harbourbridge crash has caused major traffic delays. Some north and southbound lanes closed pic.twitter.com/4TNqiMocrg

— Andrew Denney (@Andrew_Denney) February 24, 2015