Wellington Quake
© The NZ Herald
People screamed, dived under desks and sheltered in doorways as a "severe" magnitude 5.7 earthquake rocked Wellington this morning.

There have been no reports of damage so far, but workers in the central city have described multi-storey office buildings swaying for at least 30 seconds as the quake hit at 9.06am.

GeoNet said the "severe" quake struck 30km east of Seddon, in Marlborough, at a depth of 8km.

There has been a flurry of smaller shocks since the initial magnitude 5.7 quake, the strongest recorded as magnitude 3.8 at 9.38am.

At least 10 other shocks were recorded in the Marlborough area by 9.45am.

A Fire Service central communications spokeswoman said there were no reports of damage in the Wellington region so far, although an alarm activation may have been caused by the quake.

The quake shook the emergency services communications centre on the seventh floor of the police station on Victoria St in central Wellington for a good 30 seconds, she said.

There have also been no reports of damage in the upper South Island, a Fire Service southern communications spokesman said.

Upper Hutt woman Deb Norman said the first shake set the neighbour's dog barking, before a second shake hit less than a minute later.

"[It was] increasing in intensity and caused our three dogs to go crazy! The shake lasted in our home based in Upper Hutt for two and a half minutes.

"Oh well, was time for our teenage to get up - shake, rattle and roll; up time!"

Katie Russell, who was in Johnsonville, said the chair she was sitting on moved side to side.

"So my heart's still racing! Scary ... I've felt a couple of mild aftershocks too."

Twitter was flooded with tweets about the quake in the minutes afterwards.

GeoNet tweeted: "Well we all felt that at the office!"

Staff at the Ministry of Justice call centre in Wellington were "screaming in the background" when Press reporter Blair Ensor was on the phone to them when the quake struck, he tweeted.

TVNZ reporter Simon Bradwell tweeted that the quake was felt strongly in its fifth floor newsroom.

"Strong enough for most to get under their desks, first time I've seen that in over 8 years."

Ashleigh Lambert tweeted the quake was "scary".

"Phew, that was the first time I've actually considered getting under my desk for an earthquake."