The earthquake, which struck in the wee hours, destroyed buildings, roads and cut power, water and sewage connections in the biggest city of one of the world"s most earthquake-prone countries.
With the earthquake striking at 4.35 am, when most of the people were asleep, mass casualties were avoided and only two serious injuries have been reported so far.
As people fled multi-storey buildings, ten aftershocks ranging from 3.9 to 5.2 in magnitude on the Richter scale were recorded after the tremor.
Christchurch and entire Canterbury province has no power. Broken water and sewage pipes led to flooding in subsurbs. Besides this, River Avon also overflowed as the quake struck.
Travel services were suspended and the central business district of the city was closed after the quake brought down buildings filling the roads with rubble.