Shaken Canterbury residents have spent a fitful night as 190 earthquakes rattled the region after yesterday's strong aftershock.
The 5.7 earthquake hit the South Island at 6.13pm, toppling chimneys, closing a key road to Kaikoura and forcing spooked residents to sleep outside.
The 23km deep quake struck 20km southeast of Culverden, near the epicentre of last week's massive Kaikoura quake.
The worst damage, including toppled chimneys, was reported in the North Canterbury town of Waikari.
Resident Hillary Louis told Newshub the quake "was like an explosion going under the house".
"Now we are all congregated at one neighbour's house and we are all sleeping outside tonight. We can't go back in the houses because they are so badly damaged."
Louis said her street was continually being struck by aftershocks.
"We are right in the zone. Everyone is out of their houses, we've got lots of damage and they keep continuing every two minutes."
The earth split open.— AJ+ (@ajplus) November 21, 2016
This drone video shows the impact of the New Zealand earthquake on the Kekerengu fault line. pic.twitter.com/KNiMyNdWOo
Another resident, Kate McMillan, said the rolling aftershock lasted for about 30 seconds.
"I grabbed the kids and ran outside. Everyone was out there."
McMillan went back outside during a couple of the stronger aftershocks in the night.
Her children, aged 8 and 11, found it "a bit of an adventure".
"They weren't too scared. It's just part of life at the moment."
Earthquake in New Zealand turns roads into cliffs. Via Clayton Lindstrom on FB pic.twitter.com/JRi8wsfZvI— Gautam Trivedi (@Gotham3) November 22, 2016
McMillan didn't have any damage at her house and she wasn't aware of neighbours having damage.
Waikari School was opening at 10am.
Other Canterbury residents rattled by yesterday's strong aftershock described it as "horrid" and "rolling for ages".
GeoNet said 190 earthquakes hammered the region in the past 12 hours. Five were over magnitude 4.
Canterbury Civil Defence said Inland Rd, the only route connecting Kaikoura to the rest of the region, was closed because of the risk of further slips after the quake.
The road would remain closed until engineers had assessed it this morning.
The 7.8-magnitude earthquake in New Zealand on November 14 caused a six-metre shift in the seabed pic.twitter.com/jW5brR6q9a— The Telegraph (@Telegraph) November 22, 2016
A Defence Force convoy scheduled to ferry supplies into Kaikoura would be delayed.
Canterbury Civil Defence duty controller Brett Aldridge said people's safety was the top priority and staff would open the road as quickly as possible.
A Hurunui District Council spokeswoman said they hadn't received any calls from people requiring assistance.
Building inspectors would assess damage in Greta Valley and Scargill Valley today.
The quake was part of a cluster, starting at 6.10pm, ranging from magnitude 4 upwards.
More than 4000 people reported feeling the quakes on the GeoNet website.
An NZME reporter in Christchurch said the first quake hit with a jolt and then continued rumbling for some time.
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