The New Zealand earthquake has prompted an official state of emergency in Christchurch as the clean up program begins.

The 7.0-magnitude earthquake struck Christchurch at 4.35am on Saturday, ripping open a new fault line in the Earth’s surface. No-one was killed, and only two serious injuries were reported.

Troops have been called in to help police in New Zealand’s second biggest city and the state of emergency has now been extended until Wednesday. After reports of looting, a night-time curfew is being enforced.

A judge warned that people caught looting would be viewed as being “capable of anything” and could expect harsh treatment from the courts.

Schools, shops and businesses in Christchurch were closed and residents were advised to stay at home until inspections of the more than 500 buildings damaged by the earthquake have been completed.

The Christchurch clean up begins

Today, bulldozers moved into central Christchurch to begin clearing up after the quake. An estimated at two billion dollars damage has been caused and the central business district is still a no-go area.

Reportedly, 100,000 of the Christchurch area’s 160,000 houses were damaged, many beyond repair.

Power has been restored to all but about 3 500 households but the city’s wrecked underground water and sewage system are the immediate biggest problem. Christchurch residents are being advised to boil all water before use.

Prime Minister John Key said the earthquake would have a short-term negative impact on economic growth, but that loss “would be more than made up by the stimulus impact that takes place with the rebuilding programme”.