Christchurch's central city red zone has reopened a day after a sharp 5.2 magnitude earthquake forced its closure.
The earthquake struck at 2.44pm on Friday centred 10km east of the city at a depth of 11km. It was followed at 4.02pm by an aftershock measuring 3.1 in the same area and at the same depth.
All workers were cleared from the central city red zone as a precaution, though there were no reports of falling debris and no one in the area was hurt.
The Canterbury Earthquake Recovery Authority says engineers have checked indicator buildings and there has been no further significant damage as a result of the quake.
The authority says up to 1400 workers can be in the red zone on a weekday.