(Updates with Christchurch mayor quotes, more details)
WELLINGTON, Feb 14 (Reuters) - A strong 5.7 magnitude earthquake struck near Christchurch in New Zealand on Sunday, causing cliffs to collapse into the sea but no major damage to the city, which was devastated by a 2011 quake which killed nearly 200 people.
The epicentre of Sunday's quake on New Zealand's south island was 15 kms (9 miles) east of Christchurch and at a shallow depth of 15 km (9 miles), said the country's seismological body Geonet.
Geonet said there were more than 40 aftershocks.
The quake came eight days before the anniversary of the deadly 2011 quake that caused upwards of NZ$40 billion ($26.52 billion) of damage, causing much of the city to require a rebuild.
Police said there were no reports of major damage or serious injuries, but people were evacuated from several buildings and there were reports of some liquefaction.
The Christchurch City Council said cliffs collapsed in several places along the surrounding coast, spreading large clouds of billowing dust across the sea and hills.
"Obviously with a 5.7 magnitude earthquake so close to the eastern coast of Christchurch its certainly been a big shock for the city, a set back in terms of people's confidence and feeling of security," said Christchurch Mayor Lianne Dalziel.
"Our city is stronger than it was five years ago. There are going to be a lot of people out there feeling very vulnerable."
($1 = 1.5085 New Zealand dollars)