A magnitude 5.8 quake hit Christchurch this afternoon at 1:58pm, 20km north-east of Lyttelton, frightening people throughout the city.

Aftershocks continue to rock the city, with a magnitude 6.0 aftershock at 3:18pm.

NewstalkZB.co.nz has the latest from Christchurch as it comes to hand.

Send us your photos, videos and stories - Be The Reporter or email online@newstalkzb.co.nz

Latest audio can be found on our Audio on Demand page

6:00pm: If your property is damaged and requires urgent emergency repairs, call EQC on 0800 DAMAGE (0800 326 243)

If you have any welfare related issues or concerns, call the Christchurch City Council on (03) 941 8999

5:50pm: Christchurch's central city container mall will reopen tomorrow morning.

Restart has closed for the day but assessments have revealed no structural damage.

Central City Business Association Manager Paul Lonsdale says it's unfortunate as it had been a strong trading day.

He says they never come at the right time, saying if it's not Boxing Day it's just before Christmas.

Paul Lonsdale says it's certainly made shoppers feel uneasy.

5:33pm: Christchurch Airport has just re-opened.

It comes after runways, navigation systems and buildings were fully assessed.

Chief Executive Jim Boult says there has been no damage to the airport’s runways, which are now open for landings and departures.

He says the terminal is open and he expects flight operations to re-commence about 6pm.

Mr Boult is warning there will be significant delays and some flight cancellations, and it will likely be well into tomorrow before the backlog is cleared.

He says people should check with their airlines before going to the airport.

5:26pm: St John Ambulance communications has received up to 150 emergency calls since the first earthquake this afternoon.

It says paramedics have assessed and treated around 50 to 60 patients with earthquake-related injuries or issues.

All of these were minor injuries or issues, and included falls, anxiety issues, panic and stress issues.

St John says it's busy, but coping, with 14 ambulances and rapid response vehicles working in Christchurch.

5:24pm: Like many shopping centres, the Palms Centre in Shirley is closed.

The centre has been fully evacuated and all facilities including ATM machines are closed.

Staff are directing traffic around the centre to ensure shoppers return home safely.

The Palms will remain closed for the remainder of the day while thorough checks on the building are carried out by structural engineers.

5:23pm: There have been four earthquakes over five on the Richter scale in Canterbury this afternoon.

The first was magnitude 5.8 and hit just before 2pm, followed by a magitude 5.3 quake at 2:06pm.

At 2:14pm there was a magnitude 4.2, but the largest was a magnitude 6.0 and at 3:18pm.

It was followed by a magnitude 5.0 jolt at 3:50pm.

5:17pm: Petrol chain Z says there's plenty of fuel in Christchurch.

It says stocks are high for the holiday season, and there was a delivery via coastal tanker into the Port of Lyttelton today.

It says the infrastructure appears sound and is operational, so there's no need to queue or panic buy.

It says all its stations are in good shape, but three at New Brighton, Linwood and Shirley have no power.

5:10pm: The earthquakes in Christchurch today have disrupted operations in at Countdown supermarkets.

The only one that remains open is in Rolleston, while the rest are closed and in the process of cleaning up and evaluating damage.

Countdown is hoping its stores in Kaiapoi, Colombo Street and Rangiora will be opened this afternoon and evening.

Online shopping is on hold until further notice.

5:09pm: There's hope power will be restored to 26,000 Orion customers in Christchurch within a couple of hours.

Power was cut following the two large aftershocks this afternoon.

Orion CEO Rob Jamieson says the aftershocks keep tripping the lines.

"It means there isn't sort of major damage to sub-stations that could take a long time to fix, so tripping is a good thing, caused by shaking so I'm hoping within a couple of hours we'll have power back on to the vast majority of that 26,000," he says.

5:00pm: St John Ambulance has received between 130-150 111 emergency calls since the first earthquake at 1:58pm.

They've assessed and treated around 50-60 patients with earthquake-related injuries or medical issues.

All were minor injuries or medical issues, including falls, anxiety issues, panic and stress issues.

Some of these patients were taken to Christchurch Hospital, some were taken to medical centres, and some were treated at home.

4:52pm: Earthquake Recovery Minister, Gerry Brownlee, is travelling back to Christchurch this afternoon to assess the situation.

4:34pm: Some residents at Windsor Hospital rest home in New Brighton are trapped on the second floor of the building.

They're being evacuated by the Fire Service.

4:33pm: Orion says more than 26,000 customers in Christchurch's Eastern suburbs are without power.

After the first earthquake shortly before 2pm, 15,000 people were without power - that number's jumped since with the magnitude 6 aftershock.

Orion CEO Rob Jamieson says the power company's chasing its tail as it tries to reconnect people to power.

Mr Jamieson says the aftershocks keep tripping the lines.

4:28pm: GNS Science says the second quake in Canterbury was magnitude 6.0, centered 10km  east of the city and 6km deep

4:25pm: There will be no mail deliveries in the Christchurch area by New Zealand Post tomorrow.

The Christchurch Mail Centre has been evacuated as a precaution for the safety of staff and will not re-open for processing this evening.

The next scheduled New Zealand Post mail deliveries following the statutory holidays will be 28 December.

PostShops will be open tomorrow on a case-by-case basis at the discretion of individual store managers.

4:20pm: John Key has issued a statement saying his heart goes out to the people of Christchurch and Canterbury.

The Prime Minister says it will be frightening and disheartening for them to be experiencing even more earthquakes of such a magnitude, particularly this close to the holiday season.

Mr Keys says residents can be confident that the authorities are onto the situation and government resources stand ready to assist wherever needed.

Earthquake Recovery Minister, Gerry Brownlee, is travelling back to Christchurch this afternoon to assess the situation.

4:18pm: Today's quakes are causing a re-evaluation of Christmas for many.

As a result, all Anglican church services will be held outdoors this weekend.

4:11pm: Christchurch Polytech Institute of Technology has decided to close its campuses to staff and students until January 9th as a precautionary measure.

It's to give engineers sufficient time over the Christmas period to assess the buildings.

4:03pm: Civil Defence has activated the National Crisis Management Centre

4:01pm: Christchurch Airport remains evacuated, with literally hundreds of people standing outside with their luggage.

Reporter Scarlett Cvitanovich says nobody knows when they'll be able to go back inside.

"There's quite a bit of aggression out there. People are asking how they're going to get on flights in time for Christmas and are taking it out on staff at the moment," she says.

Flights bound for Christchurch are also being diverted to other cities.

3:58pm: Christchurch's mayor says the psychological impact of today's earthquake and aftershocks are big.

Mayor Bob Parker says nothing can prepare Cantabrians for more earthquakes.

Mr Parker is urging people to stay off the streets to keep them clear in case of emergency.

"Psychologically this is a tough one. People are outside buildings on streets weeping, I'm told. You can just sense the sense of 'not again, how much longer?" he told Newstalk ZB's Bruce Russell.

Mr Parker says it's a blessing there's only one report of injury.

3:55pm: Newstalk ZB's Lesley Murdoch is in Sumner, where the air is now thick .

"Just covered in dust, it was a beautiful day and it's just now all dusty, just horrible."

3:48pm: Telecom says there have been no significant disruption to its services as a result of this afternoon’s Canterbury earthquakes.

It says there was some calling congestion in the immediate aftermath of the first quake, and Telecom is now asking its customers to text rather than make mobile calls in order to ease the load.

Disruption to mains power supplies means that some equipment is operating on battery and generator backup.

Telecom says the 111 emergency call system is operating normally.

3:43pm: Christchurch Hospital, Princess Margaret Hospital and Hillmorton Hospital are all fully operational, while Burwood is on emergency power.

The Canterbury DHB says there are no reports of damage so far and no injuries to staff or patients.

A small number of earthquake-related casualties have arrived at Christchurch Hospital's Emergency Department, but there are no serious injuries amongst them.

Residents are being asked to help keep the Emergency Department clear for genuine emergencies.

3:42pm: A partly demolished building on the corner of Barbadoes and Kilmore Streets has collapsed, but the Fire Service advises there was no one inside..

A vacant house at 81 Aynsley Terrace has also collapsed, major holes in the road have been reported on Broadhaven Avenue and liquefaction has been reported in Avonside.

Earlier this afternoon: The Christchurch City Council is establishing an Emergency Operations Centre in the city, following this afternoon’s earthquakes.

A magnitude 5.8 quake struck at 1:58pm, 20km north-east of Lyttelton, frightening people throughout the city.

And the aftershocks keep rolling, with an aftershock at 3:18pm described as bigger than the first earthquake.

Newstalk ZB reporter Juliette Sivertsen is in her home in Christchurch and says this last shake felt a lot stronger than the 5.8 at 1:58pm.

"Things have fallen off and crashed over in our house. We've got little children that we're trying to get under the door frame and into a safe place. It was really, really long, very violent and we are all really shaken up at the moment," she says.

Newstalk ZB reporter Elliott Smith was also at his home in Christchurch and says he lurched for a door frame when the second large one hit.

He says the force of the quake was so strong that it knocked it off his feet before he'd reached the door.

Police are doing aerial reconnaissance to check for damage across the city.

All council buildings will be closed until they can be assessed as safe to occupy.

The council is still assessing whether water or waste services have been affected.

Police say there are no major reports of damage yet, but it's still early, and there's liquefaction in the eastern suburbs. 

One person has been taken to hospital after being injured when the quake hit Eastgate Mall.

All major shopping malls have been evacuated and closed, as has the airport.

Police say there are no serious injuries or widespread damage, at this stage.

15,000 customers are without power from New Brighton to Shirley.

Orion says power is also out in Springston in central Canterbury.

A spokesman says the outages appear to be due to tripping caused by shaking rather than damage to equipment.

It expects to have most power back on within the hour.

Civil Defence and Emergency Management is urging residents to expect aftershocks, and every time one is felt to drop, cover, and hold on.

It says to assess your home or workplace for damage and if the building appears unsafe, get everyone out.

Civil Defence is urging Cantabrians to help people who require special assistance, such as infants, elderly people, those without transportation, families who may need additional help, people with disabilities, and the people who care for them.

Another key message is not to overload phones with non-emergency calls.

It says detailed safety advice will come from local authorities and emergency services in the area and people should act on it promptly.

Scarborough rock face has suffered some collapse but this has been contained by the containers at the foot of the cliff.

The Lyttelton tunnel is open.

Police are urging drivers to slow down, saying there is significant traffic on city streets.

All available police units have been mobilised across the city to provide reassurance and check on safety and damage.

St John responded to 19 emergency calls from the first quake this afternoon.

It says all the injuries have been minor.

The majority were chest pains, people collapsing, people having seizures, panic attacks and anxiety issues.

There was one minor car accident and one person had a knock to their head.

Newstalk ZB's Brian Ashby says there's liquefaction in the Queenspark area of Christchurch.

"Again, just literally as we speak wading through water and mud that's bubbled up from under the footpath, under the road, the roads are blocked, we can;t get to the house that we are trying to get to, the sun's out, it's a glorious day but under foot it's just an absolute shambles."

The aftershocks keep coming - Philip in Shirley rang Newstalk ZB to say the first quake left him without power.

"A few of my neighbours are too but it felt to me as vicious as February 22 because it was so shallow," he says.

Newstalk ZB reporter Elliott Smith was on the couch in his Mairehau home when it struck.

"It just came and boy, it certainly had a lot of force to it. Judging by the reaction of people, our neighbours have come over, they weren't expecting anything like this at all," he says.

Since the quake, Elliott Smith says there's been several smaller aftershocks which have left people on edge.

"I thought 'I haven't felt one of these for a while' and boy oh boy it just started slamming everywhere. I looked around the room and the computer monitor was falling over and everything was just swaying from side to side," he says.

Reporter Lesley Murdoch was in Sumner when the quake hit.

"The Taylors Mistake side of Scarborough Hill seems to have taken a real hit, the dust cloud that's come off there, it's a bitumen hillside of Wakefield Ave, a whole slice of that place has come down, they had containers there anyway."

Newstalk ZB's Jo Scott is comforting her two young children after another big shake in Christchurch.

She was at home when it hit.

"It was very frightening, we've got things off the shelves at home again, I can hear car alarms going off, my husband was outside the Catholic Cathedral on Barbadoes St, there were bits of rubble coming down off that."

Newstalk ZB reporter Amanda South was at a park in Sumner when it hit and says she felt sick.

"My gut was just saying no, no, this is big one, why are we having another big one? We've all had this underlying anxiety, what is this isn't done with us," she says.

She says rocks started tumbling down the hills near where she was, people were panicking and there was dust everywhere.

"It hit me like a punch in the gut. It was very scary, very intense, and that's the worst quake I've felt in months and months and months," she says.

She says people in Sumner have been told to get out.

Reporter Juliette Sivertsen had just arrived at Christchurch International Airport, home for Christmas, when the quake struck.

She was just outside the carpark.

"I could see the cars just moving from side to side all on the building and obviously this really load roaring and rattling, quite terrifying."

Flights heading from Auckland to Christchurch have been cancelled or redirected.

Newstalk ZB reporter Nicola Grigg was due to land in Christchurch at the time of the quake and has been diverted to Wellington, before heading back to Auckland.

"I can tell you it was a very, very nervous 20 minutes sitting on the plane. Obviously everyone's bound for Christchurch and people have family and friends down there. With no communication on the plane, everyone was really scared," she says.Christchurch's Eastgate Mall was a site of panic following today's earthquake.

One shopper was in the same building, where one person was injured and required hospital treatment.

"She really shook. There was a hairdresser shop next door and all the hairspray was falling off shelves. I've never seen anything like it," he says.

He says everyone ran for the doors when the shaking started because there was nothing to climb under.

Photo: Rockfall at Sumner after today's quake (Amanda South)