Richard Williams, Sky News Online
A powerful earthquake in the southern New Zealand city of Christchurch has killed at least 65 people, while 200 others are feared trapped in damaged buildings.
The country's prime minister, John Key, revealed the death toll during a statement on the plight of the city of 350,000 people - and warned it may rise.
He told TV1 News: "It is a just a scene of utter devastation. This may be New Zealand's darkest day."
"My thoughts are also with the emergency services and everyone who is assisting in the rescue efforts."
Buildings have collapsed and vehicles are buried beneath debris, with rescue workers scrambling to help those trapped under rubble left by the 6.3-magnitude quake.
This has shaken me to the core. I'm really concerned about friends that I haven't been able to get in contact with in the city.Jo Kane, who lives on the outskirts of Christchurch
The fire service said the proximity of the quake to the city's centre meant it had caused more damage than the 7.1-magnitude tremor in Christchurch last September.
"The shake has been a lot worse, maybe not in intensity but as far as damage is concerned, and there are numerous people trapped," a spokesman said.
A police statement said: "Reports include multiple building collapses, fires in buildings in the central (city) and persons reported trapped in buildings."
Those killed are thought to include the occupants of two buses that were crushed by falling debris.
Vehicles were crushed when a car park collapsed
Pavements and roads were cracked and split, and hundreds of dazed, screaming and crying residents wandered through the streets as sirens blared throughout the city.
Christchurch Mayor Bob Parker said he was on the top floor of the city council building when the quake hit just before 1pm local time, throwing him across the room.
"There will be deaths, there will be a lot of injuries, there will be a lot of heart break in this city," he said.
"I got down onto the street and there were scenes of great confusion, a lot of very upset people."
Helicopters dumped giant buckets of water in attempts to douse a fire in one tall office building, while a crane helped rescue workers trapped in another office block.
The airport was closed and Christchurch Hospital was evacuated. Power and telephone lines were knocked out, and pipes burst, flooding the streets with water.
The multi-storey Pyne Gould Guinness Building, housing more than 200 workers, was among those that collapsed and at least 30 people are said to be trapped inside.
Television pictures showed rescuers, many of them office workers, dragging severely injured people from the rubble.
The US Geological Survey said the centre of the quake was three miles from the city at a relatively shallow depth of 2.5 miles.
A 5.6-magnitude aftershock hit shortly after seven miles east of the city at a depth of 3.7 miles.
City councilman Barry Corbett said: "When the shaking had stopped I looked out of the window, which gives a great view onto Christchurch, and there was just dust.
"It was evident straight away that a lot of buildings had gone."
Christchurch has been hit by hundreds of aftershocks since the previous earthquake struck in September.
That quake caused no deaths, but the city was still repairing the extensive damage.
:: British nationals concerned about relatives or friends affected by the quake can contact 020 7008 1500.
The airport was closed and Christchurch Hospital was evacuated. Power and telephone lines were knocked out, and pipes burst, flooding the streets with water.
The multi-storey Pyne Gould Guinness Building, housing more than 200 workers, was among those that collapsed and at least 30 people are said to be trapped inside.
Television pictures showed rescuers, many of them office workers, dragging severely injured people from the rubble.
The US Geological Survey said the centre of the quake was three miles from the city at a relatively shallow depth of 2.5 miles.
Power and telephone lines were knocked out by the tremors
City councilman Barry Corbett said: "When the shaking had stopped I looked out of the window, which gives a great view onto Christchurch, and there was just dust.
"It was evident straight away that a lot of buildings had gone."
Christchurch has been hit by hundreds of aftershocks since the previous earthquake struck in September.
That quake caused no deaths, but the city was still repairing the extensive damage.
:: British nationals concerned about relatives or friends affected by the quake can contact 020 7008 1500.
Christchurch's Mayor said he was aware of serious injuries caused by the quake