The Hanmer district in North Canterbury was shaken by two earthquakes late last night.
A magnitude 5 quake and an aftershock of 4.8 struck within a few minutes of each other about 11.30pm.
Both were both centred 35km north-east of the town, at a depth of about 30km.
There have been three more quakes measuring above magnitude 3 since the initial quake.
