There has been another aftershock in Christchurch, measuring magnitude 4.4.
The quake was centred 20km east of the city at a depth of 15km. It occurred at 4.45am on Friday.
Earlier, there was a magnitude 4.3 aftershock at 10.48pm on Thursday. Its epicentre was sited 10km east of the city at a depth of 10km.