Christchurch is bracing itself for high winds overnight, which could cause more damage to homes and buildings hit by Saturday morning's devastating earthquake.
The winds were starting to hammer parts of the region late on Sunday night.
Fallen power poles and trees across State Highway One near Dunsandel, south of Christchurch, have caused two vehicle accidents.
The Fire Service says there has been wind damage in Oxford, Culverden and Cheviot, north of Christchurch, with power lines down, and electricity cut to Oxford.
It says there have been no reports of wind damage in the inner city, but winds are gusting up to 57km/h.
The police are urging people to stay off the streets, saying 130km/h wind gusts could bring down already unstable bricks and masony.
MetService says the winds, which have caused damage in Otago, are moving towards the Christchurch area.
Damaging high speed gusts are forecast to hit the city until 6am on Monday.
The Canterbury District Commander, Superintendent Dave Cliff, says if the wind arrives, there's the risk of loose tiles and bricks and iron being blown off rooves.
He says people should not go out in the city nor drive unless they absolutely have to.
The chief executive of electricity network company Orion New Zealand, Roger Sutton, says high winds could bring down lines, causing more disruption.