4.2 quake shakes Christchurch
Christchurch has been shaken by a magnitude-4.2 earthquake this morning.
It was centred 15 kilometres east of the city and was 9km deep, GeoNet said.
The tremor was felt widely across the city.
GeoNet said the intensity of the quake, which hit at 11.51am, was "strong".
Over 500 people reported to GeoNet they had felt the quake.
Press reporter Anna Turner said she was in a dairy when the quake struck and the owner "yelled and dived under the counter".
Twitter user Deon Swiggs tweeted: "That will teach me for taking a midday shower! My first experience at being thrown about in the shower."
Another user, Desere Girdlestone, wrote: "Heart racing - shew! Sure as hell felt that 4.3 on the 2nd storey of our office in Hillsborough."
Reader Renee Craw said the quake was rattling the shelves and was quite noisy at Rebel Sport in Westfield Mall in Riccarton.
Half an hour earlier, at 11.21am a magnitude-2.8 quake was recorded by GeoNet.
It was 12km deep and centred 5km east of the city.
A Canterbury Earthquake Recovery Authortity spokeswoman said the authority had no reports of damage, and cranes were still working on the Clarendon Tower demolition.
A St John spokesman said the service had not received any reports of injuries.
St John encouraged people to check on their neighbours and family, especially those who were alone and vulnerable, he said.