A magnitude 6.1 earthquake has struck off the Kāpiti Coast, according to monitoring body GNS.
The quake struck at 7.38 p.m., 50 kilometres north-west of Paraparaumu, at a depth of 48 kilometres, causing intense shaking.
Jen Andrews, GeoNet seismic duty officer, said it was a "slab event," meaning it occurred in the tectonic plate that runs beneath the North Island.
"It was felt quite widely and strong. We've had about 50,000 felt reports over the North Island and South Island."
Andrews says aftershocks would be felt.
"We will be expecting to record aftershocks ... probably the largest would be one unit smaller, so magnitude 5. And potentially we will have some of those larger aftershocks because this event was quite deep."
Andrews says aftershocks could happen over the coming hours, and even days; People should drop, cover and hold when they did.
There was no tsunami threat, despite the quake feeling 'long and strong' she said.