UPDATED 7.00am Central New Zealand has again been rattled by a strong earthquake, a magnitude-5.3 tremor waking thousands in their beds.

Geonet says the "severe" quake struck 20km southwest of Seddon in Marlborough at a depth of 13km at 12.17am on Friday.

More than 6300 people registered feeling it with more than 400 saying it was at least strong, according to the Geonet website.

It was felt in many parts of the country as far north as Auckland and as far south as Gore.

Civil defence said it was "quite a rattle".

Far North man Steven is in Blenheim with 3500 scouts, at a jamboree.

"I knew it was an earthquake straight away. It wasn't scary, just a bit startled though."

He's in a motel rather than camping with the kids though - saying he's done his time in tents.

"The bed was shaking. The building was shaking. There was a sort of rumbling sound and it's the first time I've ever experienced an earthquake in all my 68 years."

Hutt Valley man John says it was a strong shake.

"It certainly woke me up and I was thinking, is this another large one? You just can't tell."
The quake comes less than two months after the 7.8 Kaikoura tremor, which caused widespread damage around north Canterbury and Wellington.

Though duty seismologist at GNS Bill Fry said this morning's quake had nothing on the Kaikoura quake.

"It's much much much smaller, much less significant than the Kaikoura 7.8."