A magnitude-5.3 earthquake has struck 40 kilometres southwest of Haast.
GeoNet said the shake happened at 7.38am today and was five kilometres deep.
GNS Science described the quake's intensity as severe and reported it had been felt as far afield as Dunedin.
More than 270 people have so far reported they felt the quake to GeoNet.
Of those, five considered the quake "strong", while 29 thought it was "weak".
The remainder classified the quake under the category "largely observed".
Mary Gray felt the quake in Clyde, Central Otago.
"We were still in bed with our morning tea and the paper when the first quivers started, followed by a definite shaking of several seconds," she said.
"As 'refugees' from Christchurch, we're probably super-sensitive to quake movements, and didn't enjoy it one bit!"
Lauren Sleeman said: "It was a decent shake but thankfully not the abrupt, jarring, break-things type, more the big rumble type.
"There is no wind on this beautiful morning here in Wanaka but the trees swayed as if in a wee breeze!"
Eamonnd Johnston, of Johnston Motors, was in his Haast Junction home at the time of the shake.
He described it as "hardly even a wobble".
"I was wandering around my home like a lost sheep when it hit. It was just a rumble and a rattle and it was over before I realised what it was," he said.
Johnston said it did not cause any damage to his home or the town as far as he knew.
Some Twitter users said they felt the quake, with one saying: "Wow, you could hear that one rolling through the hills into Arrowtown, shaky start to the morning."
Another person said their mum "heard the roaring and thought, that's an early plane!"
- © Fairfax NZ News
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