Update at 7:20 pm ET — New Zealand geologists have changed their estimate of the size of earthquake that hit near the city of Christchurch, saying it was magnitude 7.1. That brings it closer to the magnitude 7.0 quake estimated by the U.S. Geological Service several hours earlier.
Update at 4:43 pm ET — While there appears to be much destruction and disruption in Christchurch, there so far has been a surprisingly low number of reported casualties in New Zealand following the magnitude 7.4 earthquake.
From the news web site stuff.co.nz.
BREAKING NEWS: A massive 7.4 magnitude earthquake has hit Christchurch and the wider South Island, causing widespread damage, two serious injuries and power cuts to most of the city.
The quake was centred 30km west of Christchurch and 33km underground. It hit at 4.35am and there have been many reports of damage, including buildings being flattened and a road being ripped up.
It was felt widely across the South Island, most strongly in Christchurch and Timaru, and there have also been reports of the quake being felt as far as Wellington. Several aftershocks have been felt.
There have been unconfirmed reports of looting in central Christchurch following the quake.
Update at 2:45 pm ET — There've been numerous reports of aftershocks following the magnitude 7.4 earthquake in New Zealand Saturday morning, local time. The web site stuff.co.nz has a photo of a building with its roof collapsed which appears to be in a business district.
Update at 2:30 pm ET — Commenter Karthik BR on this post reports a sister in New Zealand who is staying o the coast says that houses there are "fully flooded." That's an interesting report, especially since there's been no tsunami warning with this massive earthquake.
Update at 2:22 pm ET — The U.S. Geological Survey has reduced its measurement of the earthquake to magnitude 7.0. But New Zealand's earthquake experts are calling it was a magnitude 7.4. We have decided to go with the New Zealand measurement, the guidance from our science team being that the New Zealand seismic detectors are probably more accurate on this one due to proximity.
Update at 2:14 pm ET — Radio New Zealand's presenter or anchor on its national service just said that Christchurch's airport is closed as officials inspect it for damage, which sounds like standard procedure. He urged listeners to stay in doors because of the power outage and debris in the streets.
But in an interesting journalistic move Radio New Zealand appears to be sticking to its regular programming. A children's show called "Magic Muffin" is streaming as I write this. Not sure meaning we should take from this.
Update at 1:58 pm ET — An NPR colleague who is monitoring Radio New Zealand sends this:
National emergency officials reporting significant road damage, many buildings damaged, most of Christchurch is without power and sewer and water pipes have disrupted in many places.
You can listen to the Radio New Zealand live stream for yourself.
Update at 1:52 pm ET — A report on the web site of the Nelson Mail indicates that there is damage from the magnitude 7.2 earthquake in New Zealand 20 miles northwest of Christchurch.
BREAKING NEWS: A massive 7.4 magnitude earthquake has hit New Zealand's South Island, causing widespread damage and cutting power.
The quake was centred 30km west of Christchurch and 33km underground. It hit at 4.35am and there have been many reports of damage, including buildings being flattened.
It was felt widely across the South Island, including Christchurch and Timaru, and there have also been reports of the quake being felt as far as Wellington. Several aftershocks have been felt.
The rail network in the South Island has been shut down while it is inspected for damage.
Colleen Simpson, from Christchurch, said everyone was out in the street in their pyjamas looking scared and worried. There was no power, buildings were down and the mobile network was failing.
"Oh my God. There is a row of shops completely demolished right in front of me," she said.
— original post below —
New Zealand was rocked by a very strong earthquake that's being reported as a magnitude 7.2 by the U.S. Geological Survey.
The earthquake was 20 miles west of Christchurch and was very shallow, only 10 miles into the earth's crust. As a general rule, the shallower the quake, the more potential for damage.
The earthquake occurred at 4:35 am local time so many people were asleep when it happened. At this point I'm not seeing reports of major damage or casualties.
An excerpt from the New Zealand Herald web site:
A Timaru resident told NZPA he was awakened by the shaking. His house was groaning and a bedside lamp crashed off its table.
Radio New Zealand said listeners were reporting particularly strong effects in Christchurch, with one saying his house "turned upside down" with crockery breaking.
A caller to a radio station, Newstalk ZB in Christchurch reported that the earthquake caused major upsets in people's homes, bells in bell towers to rine and huge flash of lights that were presumably electrical transformers exploding.
We'll continue to update as we get more.