Powerful quake rattles New Zealand city

WELLINGTON - A magnitude 5.5 tremor rattled the quake-prone New Zealand city of Christchurch on Monday, sending people fleeing from buildings, and boulders tumbling down hillsides.
Police said there were no initial reports of injuries from the quake, which comes almost four months after a magnitude 6.1 earthquake killed 181 people and caused extensive damage across the city.