The evacuation, via sea, of tourists stranded in Kaikoura is still a day away.
The HMNZS Canterbury left Auckland last night, bound for the town on the east-coast of the South Island - one of the worst-hit by the 7.5 magnitude quake that struck shortly after midnight.
However, the navy vessel wasn't expected to begin evacuating people till first light Wednesday morning.
Air commodore Darryn Webb, acting commander join forces New Zealand, said the ship would be picking up emergency supplies on its way to Kaikoura.
Slips and slides along the main roads into the popular tourist town have made road access virtually impossible - with SH1 and the main trunk rail line buried.
Information from the latest Civil Defence update indicated there had been between 80,000 to 100,000 landslides in the area - with at least one large landslide on the SH1 south of Kaikoura and at least four large ones to the north.
The railway line had also bent and shifted across the highway towards the ocean, a number of buildings had collapsed and there were also reports of an unconfirmed number of injuries.
Some 600 people are holed up in a local marae, where a local welfare centre has been established, however, emergency personnel estimate the town only has three more days of water supply left.
Air evacuations began yesterday afternoon, but the majority of evacuees were likely stuck in the town till they could be evacuated via sea on Wednesday morning.
Yesterdawy afternoon four NZDF helicopters were deployed to Kaikoura to help move people and resources.
Staff members from the Civil Defence Emergency Management team, NZ Police and Red Cross personnel were also on their way to join the Urban Search and Rescue teams that left earlier in the day.
The latest Civil Defence update said the small town had severe damage to its communication systems, roads, water and sewerage infrastructure.
While the tsunami warning has been cancelled the Civil Defence said it was important to still take care.
"There is no longer any tsunami threat to any area of NZ. However coastal areas may have unusually strong coastal currents or sea level fluctuations for some time and we continue to advise people to take extra care around the water."
Civil Defence Emergency Management Director, Sarah Stuart-Black said it was important to keep an eye out on family and friends.
"If it's safe for you to stay in your home or return home, then do so. Look after your neighbours and loved ones and remember to drop cover and hold during aftershocks.
"Civil Defence and Emergency Management groups across the country have spent today working with and checking on their communities. New Zealanders are shaken but are coming together and supporting each other. If people have tried all available contact methods to reach loved ones and been unable to do so they should contact their local Police station."
Meanwhile, St John urged people to keep in contact with family and friends as a rough weather front hit many of the already quake-battered areas.
A National Crisis Coordination Centre was in operation overnight and the service was also helping move patients out of Kaikoura as necessary.
•Expect aftershocks and remember to drop, cover and hold.
•Look after yourself and get first aid if necessary. Help others if you can.
•Building assessments should be done before buildings are opened for normal use, particularly in areas which experienced strong shaking such as the CBD areas of Wellington, Christchurch and Blenheim.
•Watch out for fallen power lines or broken gas lines. Stay out of damaged areas.
•Listen to the radio for updated emergency information and instructions.
•Do not overload phone lines with non-emergency calls. Text friends and family to see if they are OK.