Christchurch earthquake timeline

5:31pm: John Key has arrived at the Civil Defence Headquarters in Christchurch.

5:29pm: Civil Defence Minister John Carter has told Larry Williams there is a very strong Civil Defence unit in Christchurch and they are confident they will have the resources to get through this disaster.

5:26pm: All Christchurch BP stations are closed.

5:25pm: The CTV building was flattened in today's earthquake and it is understood there were people inside at the time.

5:24pm: There have been nine aftershocks since the first one at 12:51pm this afternoon.

5:18pm: St John spokespoerson Michael Brook told Larry Williams ambulance resources are on their way to Christchurch.

Michael Brook spoke to Larry Williams

5:13pm: Newstalk ZB reporter Scarlett Cvitanovich told Larry Williams from the Civil Defence base, the aftershocks are continuing and Newstalk ZB reporter Jo Scott has been out in the suburbs and says the extent of the damage is far worse than that following the 7.1 September 4 earthquake.

Scarlett Cvitanovich and Jo Scott spoke to Larry Williams

5:08pm: Christchurch mayor Bob Parker says all available resources from around New Zealand are enroute to the city. He is reminding people about triage centres such as that in Latimer Square.

Mayor Parker says he is not willing to speculate on numbers of lives lost.

5:05pm: Australia has sent a 40 person search and rescue team to Christchurch.

Prime Minister Julia Gillard says she spoke with John Key this afternoon about what help Australia could offer.

Attorney-General Robert McClelland says the search and rescue team comes from New South Wales and is aboard a defence plane on its way to Christchurch.

5:04pm: 15 emergency vehicles are on their way to Whenuapai Air Base to urgently fly to Christchurch and motorists hearing that way are asked to free up the fast and middle lanes.

5:02pm: Students and staff at the University of Canterbury are being marshaled onto the Ilam Field and arts carpark.

The University Health Centre is open with two doctors present.

5:00pm: Newstalk ZB's Tim Dyer is in Latimer Square and says it has been set up as an emergency hospital.

4:56pm: Newstalk ZB reporter Amanda South has just emerged from a media conference with mayor Bob Parker and she says he is referring to "numerous fatalities".

Amanda South spoke to Larry Williams

4:44pm: One of the buildings to sustain major damage is the multi-storey Pyne Gould Guiness building on the banks of the Avon River.

There were numerous people working inside at the time and 24 people are currently being rescued from the 17th floor through the window. The stairwell has collapsed and the window is the only way out.

4:40pm: Google has created a People Finder for people in Christchurch http://bit.ly/fRgP6H

4:32pm: Civil Defence Minister John Carter says there are good lines of communication with the Civil Defence headquarters in Christchurch.

They are working closely with the police and army.

The most important message he wants to send out is that people need to make sure they are safe and their neighbours, friends and family are safe. They should move out of areas where significant damage has occurred.

People should expect further aftershocks.

Listen to the full media conference

4:26pm: Deputy Prime Minister Bill English has addressed a news conference saying the Government is totally committed to doing everything it can to help the people of Christchurch.

Prime Minister John Key has left for Christchurch.

Cabinet will meet again in a couple of hours to reassess the situation.

On the ground, emergency services are gathering a picture of the scene, doing so has been hampered by telecommunication lines being down.

Police are now working with the Defence Force to evacuate central Christchurch and will establish a strong prescence there.

Australian Prime Minister Julia Gillard has offered to send personnel and that offer has been accepted.

Reports of death cannot yet be confirmed.

Ambulances from around the South Island are on their way to Christchurch.

Phone lines are operational but there is significant overloading and Mr English asks that people use texting where possible.

4:24pm: Deputy Prime Minister Bill English is about to address a news conference.

4:23pm: All South Island hospitals except for Invercargill, have been evacuated to make room for Christchurch victims.

4:22pm: Search and rescue teams from the Bay of Plenty/Waikato region have been dispatched to Christchurch.

4:12pm: The aftershocks are continuing. Newstalk ZB reporter Scarlett Cvitanovich has just walked up Madras Street in the central city and says it is flooded with mud and liquefaction coming from the ground.

4:10pm: Police are reassuring Christchurch residents, the 111 service is still working despite some people experiencing difficulties. They say due to overloaded lines, it might take some time to get through due to network damage.

4:05pm: Update of key points to hand:

Lyttelton Tunnel is closed. SH1 north and south is open.

Christchurch International Airport is open for emergencies only. Air NZ will not fly until 7pm at the earliest.

There is damage to the port. The extent of this is not yet known.

All trains from Picton-Ashburton have been halted.

Transpower has no major issues but Orion has major outages.

People must boil water before drinking and phones to be used sparingly.

4:01pm: People in the Selwyn District are being urged to check on friends and family. The north Canterbury district seems to have been spared the worst of the earthquake with no reports of injury so far.

Anyone with concerns can contact the council on (03) 347 2800 or (03) 318 8338.

3:56pm: The fire service is mobilising its two North Island urban search and rescue task forces following the earthquake. Its third task is based in Christchurch.

National commander Mike Hall says the quake is a national disaster and the fire service is responding with all its resources.

Fire appliances and personnel from other parts of the South Island are being sent to Christchurch, others from further afield and being prepared for mobilisation.

3:53pm: Civil Defence Minister John Carter still cannot confirm any fatalities, but says there are unconfirmed reports.

3:49pm: Cantabrians are being urged to stay at home and to keep travel to a minimum.

3:45pm: Civil Defence says Christchurch Hospital is operational, with only one ward damaged.

It says the damage from the earthquake appears to be centralised in the central city.

Christchurch airport is open for emergencies only. It is closed for domestic flights pending an inspection of the runway.

Civil Defence director John Hamilton says the cell phone network is suffering under the load of people trying to get in touch with loved ones and colleagues.

3:43pm: Public are advised to text, not call, to get in touch with relatives and phones should be used sparingly.

3:37pm: A cordon has been placed around central Christchurch and mayor Bob Parker says everyone needs to evacuate the CBD.

3:34pm: The Lyttelton Tunnel is closed and the New Zealand Transport Agency is reporting major damage to local roads in Christchurch, as well as liquefaction and surface flooding.

The agency reports that the Rakaia Bridge on State Highyway One, south of Christchurch and the Waimakariri Bridge on State Highway One north of Christchurch are both open.

The NZTA advises motorists only travel if essential and use extreme caution when driving.

3:33pm: The walking wounded are asked to make their way to medical clinics, to free up Christchurch Hospital.

3:27pm: Jetstar has suspended its flights in and out of Christchurch, Queenstown and Wellington and Auckland. A spokesperson says passenger safety is Jetstar's main priority and staff are working with airport authorities regarding the status of flights. The flights have been suspended until further notice.

3:22pm: Mayor Bob Parker has just spoken to Danny Watson. he has declared a state of emergency. He confirmed buses have been trapped by debris from falling buildings. The main message he has is for residents to stay calm. They are trying to contact people in far-reaching parts of Canterbury.

He says make sure water is boiled and do not flush toilets. He says no one could have contemplated what is unfolding. Every few minutes, he is feeling trembles under his feet.

He says there are thousands of people who need to get out of the city. Roads are live lines, he says. The hospital should be ok, he says.

"Keep travel to a minimum. Do what you can around your area. Life as we know it, has come to an end here, again," is his message to Canterbury.

Terrible reports are coming to Mr Parker now. He says this is a day which will be recorded as a very sad day.

3:19pm: The aftershocks are continuing following this afternoon's 6.3 shock. Thirteen minutes later, there was a 5.7 shock and then at 2:37pm, a magnitude 3.4, and at 2:50pm at 5.5. GeoNet says there will be aftershocks for some time yet.

3:11pm: A triage centre has been set up at the Sanitarium factory in Papanui.

Manufacturing manager Geoff Davies says there are three ambulances there waiting to treat anyone who is injured.

3:09pm: The 111 phone system in Southland is out of action. Civil Defence says anyone needing urgent assistance from the police must phone their local station direct.

3:08pm: The manager of Christchurch's Central Business Association says the city has been devastated.

Paul Lonsdale says the damage is far worse than in September or in December.

3:06pm: Newstalk ZB's Jo Scott says when she went to retrieve her children from school, there was evidence of liquefaction over the school field. She says the damage to her home is extensive.

2:57pm: A Christchurch resident, Nicky was speaking to Newstalk ZB's Danny Watson when the latest aftershck hit at 2:50pm. She was stuck in gridlock traffic on the open highway to Woolsten and says her car was shaking. She told Danny "it's a big one" and described it as awful.

2:51pm: A level three emergency has been declared by the Civil Defence, the biggest possible for a regional disaster.

2:50pm: Another aftershock is happening right now.

2:45pm: Phil Goff has spoken to Danny Watson from Christchurch's Hagley Park. He was in the airport when the quake struck and he says it shook and things fell of the shelves. He says he too, has been informed there have been fatalities reported.

He is on his way to the Civil Defence headquarters and says the whole country needs to get behind Christchurch.

2:43pm: Police say multiple fatalities have been reported at several locations in Christchurch CBD. Police District Communications Manager Steven Hill says there were deaths after two buses were crushed by falling buildings. He says other reports include multiple building collapses, fires in buildings in the central city and persons reportedly trapped in buildings.

2:36pm: Cantabrians are advised to not drink tap water.

2:35pm: The Newstalk ZB office in Christchurch has been evacuated.

2:30pm: Parliament has risen for the day as a mark of respect for those affected by the devastating earthquake in Christchurch, as the Government swings into action to assist.

2:29pm: The TVNZ building in Christchurch has been seriously damaged and has been fully evacuated. Spokesperson Andi Brotherston says there are big cracks and the windows are broken. Staff are not allowed back in and she says the building beside them has collapsed.

2:24pm: Confirmation the Cathedral of the Blessed Sacrament in Christchurch has been extensively damaged.

The cathedral, in Barbadoes Street, has been in place for nearly 150 years.

It is currently closed to the public following damage after the initial Septemeber 4 earthquake.

A Catholic Church spokeswoman says the extent of the damage is unclear but it appear domes may have been knocked off.

2:23pm: A Newstalk ZB caller told Danny Watson the Knox Church is now just a wooden structure with its bricks having fallen down.

2:21pm: Injuries are confirmed and fatalities cannot be ruled out as emergency services are put to the test in Christchurch.

Police Minister Judith Collins says police are having a difficult time.

2:18pm: It appears the Government will call from help from the Defence Forces to help recovery efforts in Christchurch. John Key says this is a very worrying situation.

2:13pm: Following outages to our AM frequencies, Newstalk ZB is now broadcasting on 91FM, 97.7FM and 106.5FM in Christchurch

2:05pm: Aftershocks continue this afternoon and the biggest so far was a magnitude 4.5 tremor at 1:21pm, almost 30 minutes after the initial shock. It too, was five kilometres deep and centred 10km east of Diamond Harbour.

2:03pm: Prime Minister John Key has addressed Parliament. He has plans to hold an emergency Cabinet meeting at 3pm and will then fly to Christchurch to assess the damage for himself.

He says the concern is that the quake has hit at a time where Cantabrians were going about their daily duties.

He asks people should make every effort to contact their loved ones.

2:02pm: The national Civil Defence bunker has been activated.

1:54pm: Mayor Bob Parker has spoken to Danny Watson and has urged people to stay off the roads. He spoke from the art gallery where they are launching their effort. he says there is significant damage in the central city.

He says there are reports of some very seriously injured people and wants people to check on their neighbours.

1:48pm: Christchurch airport is closed and chief executive Jim Boult says the terminals have been evacuated and he's not aware of any casualties at the airport.

""The airport will be closed until we carry out checks of the runway and following that that will enable us to open the runways for emergency flights," he says.

1:43pm: A caller to Newstalk ZB says there is major damage - worse than that seen in the initial earthquake. He told Danny Watson, the CBD is being evacuated. He says people are trying to get out of the area as quick as they can. There are buildings that have collapsed and there's fear of more buildings falling in the central city.

1:42pm: Parts of the Christchurch Cathedral have fallen down and newstalk ZB reporter Scarlett Cvitanovich says there is dust covering everything in the central city.

1:39pm: There are unconfirmed reports one person has been killed in today's earthquake. A body has been found in the RSA in Wakefield Avenue.

1:38pm: Transpower has confirmed the power is out in parts of Christchurch, including the Central Business District.

It has inspectors out on the job checking equipment that tripped out during the quake.

Telecom has confirmed phone services are down in Christchurch and it is working to restore services as soon as possible.

The Civil Defence bunker at Parliament has been activated follwing the quake.

Civil Defence Minster John Carter is due to address media shortly.

A caller told Newstalk ZB she felt the shake in Dunedin.

"It came on completely unexpectedly. We've got a dog who picked the last one and he just froze in the middle of the lounge. We've got wooden Venetian blinds and they banged and crashed. No damage but it sort of rolled, and then almost stopped and then we had a little bit longer," she told Danny Watson.

Newstalk ZB's Jo Scott says the quake felt bigger than the 7.1 earthquake on September 4, 2010.