A sharp magnitude 5.7 earthquake and multiple aftershocks rattled Wellington and the top of the South Island on Friday.
The quake at 9.06am in Cook Strait between Seddon in Marlborough and Wellington was 8km deep and lasted for about 20 seconds. It was felt as far south as the Buller district and Taranaki in the north.
Wellington office worker Jill Turquet said she leapt under her chair and covered her head with her arms when the quake hit.
"It felt like rolling movement to begin with and then it really shook the building. Very frightening. I guess I panicked and I went under my chair in the turtle position."
Earthquake engineers spent the morning assessing civic buildings in central Wellington, but found no damage.
Aftershocks continued throughout the day, including a magnitude 4.5 quake near Seddon just after 3pm at a depth of 16km.
Wellington Civil Defence head Bruce Pepperell said Friday's quake is a wake-up call. He said the tremor and recent wild storms are reminders to people to ensure that they are prepared for a big disaster.
"I think it's just a great reminder for people to ask themselves: are they prepared, do they have water at home, do they have sufficient food to last them three days, do they have a grab and go bag in the office with some decent stout walking shoes so in the event that we did have a significant problem they were able to get home."
Mr Pepperell said it's not uncommon for quakes of magnitude 5.7 to strike the capital.
Meanwhile, Wellington City Council said there is no damage to the Town Hall, which is to close for a strengthening project in September this year. The work will take three years and cost $43 million. The council said any concerned building owners should get an earthquake engineer to check their property.
KiwiRail said speed restrictions were put in place on a number of bridges and tunnels between Otaki, north of Wellington, and Kaikoura after the initial quake, but were lifted once inspections were completed. Wellington commuter services were not affected.