A small dairy is damaged in Christchurch following a magnitude 5.1 aftershock that rattled quake-weary residents last night.
The shake hit at 9.47pm, 10km east of the city and was 10km deep, making it one of the strongest since the horrific 6.3 earthquake on February 22 which killed an estimated 182 people.
A Civil Defence spokeswoman said there were no reports of injury, but Civil Defence had received one confirmed report of damage to a small dairy in suburban Christchurch.
A cordon was being established around the building and a further assessment of its condition would be made in the morning.
A quick inspection of buildings in the inner city had shown that some loose masonry has fallen, but a full assessment would also be made in daylight, the spokeswoman said.
The 5.1 aftershock was one of three to hit the city in quick succession.
It was preceded by a quake measuring 3.0 at 9.43pm, 10km west of Lyttelton, at a depth of 5km, and followed by another measuring 2.9 at 10.05pm, 10km east of Christchurch, at a depth of 11km.
One source told NZPA the first tremor was what Christchurch residents had become accustomed to as a ``fairly standard'' aftershock, but the second 5.1 jolt was much stronger and lasted a lot longer.
Many aftershocks have been recorded since the ``big one'' of February 22.