Christchurch has been shaken by a moderate aftershock this evening.

The 17km-deep magnitude 3.8 quake struck 10km east of Christchurch at 8.22pm. More than 500 felt reports have already been submitted to GeoNet.

The tremor comes three days before the fifth anniversary of the deadly February 22 quake, and less than a week since the 5.7 magnitude Valentine's Day aftershock.