The New Zealand city of Christchurch has been rocked by a strong aftershock.
Witnesses say the magnitude-five quake lasted between 10 and 20 seconds and shook buildings in the city centre.
The tremor appears to be an aftershock following last month’s powerful 7.1-magnitude quake, which caused widespread damage in the city.
New Zealand’s geological agency, GNS Science, says it was centred 20 kilometres west of Christchurch and may have caused some minor damage.
But a spokesman for Christchurch Police says they have yet to receive any reports of damage or injuries.
The Canterbury region has been rocked by hundreds of strong aftershocks since the devastating earthquake on September 4.
Thousands of buildings were destroyed or damaged in the quake, and it is estimated the repair bill could be as much as $4 billion.
