The quake took place at around 12:30am GMT at a depth of 8.3 kilometers, and was initially measured at 6.8, but was later downgraded to 6.2 by USGS.
Meanwhile GeoNet, the official source of geological hazard information for New Zealand, measured the latest quake at 6.3 and said its depth was around 35 kilometers. At least two people were killed following the initial quake which struck New Zealand just after 11:00am GMT on Sunday. People were forced to flee uphill fearing tsunami waves as tsunami warning sirens predicted up to five meter high waves. Emergency workers went door-to-door evacuating people.