Cantabrians were tonight shaken by the largest aftershock to hit the region since July.
The 4.6 tremor (initally reported by Geonet as 4.7) struck at 9.15pm. It was centred 15km west of Christchurch, at a depth of 10km.
The shake was the strongest aftershock experienced in the region since a 4.8 quake on July 6, 2012.
The quake caused a flurry of online traffic that overloaded Geonet's website and many took to social media to comment.
A Twitter user said: "Well that one got me out of my chair. I think I'm out of practice."
Another user outside of Christchurch tweeted: "That was a goodie Chch felt that in Ashburton - very out of practice. Heart just calming down."
There were no reports of damage or injury.
- © Fairfax NZ News