WELLINGTON, New Zealand » An earthquake has shaken the New Zealand city of Christchurch, damaging some buildings but causing no injuries.

The magnitude 4.9 temblor struck Sunday morning as shoppers thronged the South Island city for post-Christmas Day sales.

Police say masonry and glass fell to the streets from buildings that were damaged, but no one was hurt.

The earthquake is the latest aftershock from a 7.1 magnitude quake that hit Christchurch on Sept. 4, causing extensive damage and some injuries. It also came a few hours after a magnitude 7.3 quake struck under the sea near Vanuatu.

New Zealand and Vanuatu are situated on the Pacific "ring of fire"—an arc of earthquake and volcanic zones stretching from Chile through Alaska and down through the South Pacific.