WELLINGTON, Nov. 14 (Xinhua) -- New Zealanders were still evacuating their homes late Monday after a burst quake dam sent a "wall of water" down a major river system blocked by a deadly earthquake earlier in the day.
The wall of water was sweeping down the Clarence River, in the Marlborough region in the northeast of the South Island, after breaking through the earthquake debris that had slipped into the river, said a statement from the Marlborough Civil Defence agency.
Water had been banking up behind the slip, about 10 km to 12 km upriver from the mouth, since the 7.5-magnitude quake struck after midnight and broke through the dammed-up debris late Monday afternoon.
Emergency services had held fears for a group of 16 rafters on the flooded river, but they were later found safe.
About eight to 10 houses were situated around the river mouth and a few others scattered up river.
Emergency services had succeeded in restoring power to the tourist town of Kaikoura, on the northeast coast of the South Island, but roads to the town remained blocked by landslides.
The government confirmed about 1,000 tourists were stranded in Kaikoura, a popular tourist destination famed for its coastal scenery and whale-watching activities.
Police issued a statement confirming two deaths as a result of the quake.
One fatality occurred a property at Mount Lyford, north of Christchurch, on the east of the South Island, and the other at a reported collapsed property in Kaikoura.
TVNZ showed footage of Prime Minister John Key and Acting Civil Defence Minister Gerry Brownlee surveying the damage to Kaikoura from an air force helicopter.
"It's just utter devastation, I just don't know...that's months of work," Key told Brownlee and pilots.
Key and Brownlee estimated the clean up would run into the hundreds of millions of dollars and clearing the debris and blocked roads could take months.
Navy supply ship HMNZS Canterbury would support the ongoing response in the Kaikoura region, Brownlee said in a statement later.
The region had suffered extensive damage to essential connections and basic infrastructure.
"The widespread destruction caused by the magnitude 7.5 earthquake and subsequent aftershocks will take considerable time and resources to repair," said Brownlee.
"Our immediate priority is ensuring delivery of clean water, food and other essentials to the residents of Kaikoura and the estimated 1,000 tourists in the town," he said.
The New Zealand Defence Force was delivering the essential items on its NH90 helicopters and on board HMNZS Canterbury.
Other areas affected by the earthquakes and landslideshad adequate communication and supplies.
"The economic impact on earthquake-affected areas will also be assessed in the coming days," said Brownlee.
"Agencies will continue monitoring the situation closely. The public should be advised that aftershocks will continue to occur."
The Ministry of Civil Defence and Emergency Management (MCDEM) said local state of emergency had been declared in Kaikoura and the neighboring Hurunui district.
"Civil Defence and Emergency Management groups across the country are sending people to the region to help," MCDEM management director Sarah Stuart-Black said in a statement.
Key and Brownlee said in a televised press conference earlier Monday that it was impossible to rule out further fatalities.
"On the very best information we have at the moment, we think it's only likely to be two, but of course there are isolated parts of the country in which we don't have perfect eyes on so we can't be 100 percent sure, but we're not aware of any that we're not reporting," said Key.
Structural engineers were also checking buildings in the capital, Wellington, where the quake was felt strongly.
The quake was centered 15 km northeast of Culverden, on the east of the South Island, and struck at 12:02 a.m. on Monday, according to the government's GeoNet monitoring service.
It is being followed by many aftershocks, the largest of them a magnitude of 6.3.
GeoNet scientist Sara McBride said the quake was the largest recorded in New Zealand since a magnitude 7.8 quake in the Dusky Sound, in the southwest of the South Island, in 2009.
"We can say one thing with certainty: there will be more earthquakes to come in this area," McBride said in a statement.
"It looks like we've got two separate but related quakes going on. Our reports indicate that the combination of these two quakes lasted two minutes, with the most severe shaking at around 50 seconds. It was widely felt throughout both the North and South Islands. It looks like one was a strike-slip and the other was a thrust fault."
A tsunami warning from Wellington, on the North Island, to Banks Peninsula, on the east of the South Island, was cancelled late Monday afternoon, said the MCDEM.
New Zealand is frequently rattled by earthquakes, most of which do no damage and cause no injuries, but Monday's tremor brought back memories of the 6.3-magnitude quake that killed 185 people in Christchurch in February 2011.
