Two dead after powerful earthquake strikes New Zealand's South Island and triggers a tsunami.

Two people have died and a tsunami has been triggered after a 7.5 earthquake struck New Zealand’s South Island just after midnight.

The US Geological Survey believe the quake hit around 95km/h from Christchurch which was left in ruins by a 6.3 tremor just five years ago.

The BBC reports the tsunami arrived two hours after the earthquake, causing officials to warn residents along the east coast to seek higher ground.

Images of the quake have flooded social media as residents share the devastation that has rippled across the South Island.

The New Zealand Herald reports the tsunami warnings have now been lifted but residents are still warned to stay away from the shoreline.

New Zealand’s Prime Minister, John Key, relayed that all sixteen regions had activated civil defence requirements and that all residents should continue to follow safety advice.

Prime Minister Key is also said to have confirmed the two deaths of individuals who are yet to be identified.

It has been reported that many homes have been left without power following the quake.

Wellington shipping workers who were forced to flee told The New Zealand Herald they watched as the floor of the shipping terminal cracked and water flooded beneath them.

"It was just panic stations," said one worker.

"Water was coming up from the wharf, we had about five seconds to evacuate."

The Herald Sun reports Wellington city-centre workers have been asked to stay home as city officials warned some buildings were showing signs of structural stress.