Here is photo after an earthquake struck on Dec. 23, 2011. REUTERS

(Reuters) - A series of strong earthquakes hit the New Zealand city of Christchurch Friday, sending goods toppling from shelves, causing rockfalls and driving terrified residents from buildings 10 months after a quake killed almost 200 people in the city.

Christchurch police said there were no reports of casualties or widespread damage, although one person had been reported hurt at a shopping mall and taken to hospital.

An initial 5.8 magnitude earthquake was centered 20 km (12 miles) northeast of the city at a very shallow depth of 8 km (5 miles), according to New Zealand's civil defense. It was followed by a series of strong aftershocks, one of a 5.3 magnitude, but no tsunami warning was issued.

The tremors struck as shoppers thronged malls in the lead-up to Christmas and prompted many residents to flee the city, clogging roads.

It was incredibly violent, one caller told Radio New Zealand.

All the water in my birdbath slopped out and I could hear everything falling over inside. When I walked inside, the cat streaked out the door, ornaments were all over the floor, contents of the pantry were lying on the floor, a little bit of smashed glass and picture frames lying over.

Christchurch, the largest city in New Zealand's South Island, is still recovering from a quake measuring 6.3 which killed 182 people in February and caused up to NZ$20 billion ($15.5 billion) in damage. A strong but less damaging quake struck Christchurch in September last year.


Christchurch Mayor Bob Parker said the series of shakes had shattered the nerves of people who had been slowly getting their lives back to normal.

It has been a long hard road, 15 months ... and people had dared to hope that the aftershocks were over, said Parker.

I think there will be more damage to buildings, nothing significant, no major collapses just little bits of more debris.

It's terrible timing, you can't underestimate the impact of this on people on the psychological level, they've been exposed to so much and it felt like it was getting better, and it just puts the work back, the repairs back, the rebuild back.

Ambulance services said they treated 18 people for panic attacks and anxiety.

Large areas of Christchurch's central business district are still off-limits after the February quake, which toppled the city's famous cathedral, as well as shops, homes and office buildings.

About 6,000 homes in the city were condemned after the February quake.

The latest quake caused some large rock falls in the hills around the city but none had fallen onto houses or roads around the nearby port town of Lyttelton which was extensively damaged in the February quake.

There's not a heck of a lot of buildings left to wreck, to bring down in an earthquake, to be perfectly honest, said the town's chief fire officer, Mark Buckley.

Four people had to be rescued after becoming trapped at a beach by a rockfall, police reported. Two buildings damaged in the previous quakes had collapsed, they added.

Aerial footage showed clouds of dust rising from seaside suburbs under sunny summer skies.

The region's main power supplier said up to 15,000 customers were without power, mostly after circuit breakers were tripped.

Christchurch International Airport was evacuated as a precautionary measure while the terminal and runways were checked.

The New Zealand dollar briefly dipped to $0.7725 from $0.7740 in thin trading after news of the quake, before recovering. New Zealand stocks cut pared gains to trade up 0.14 percent.

New Zealand straddles the boundaries of the Indo-Australian and the Pacific tectonic plates and is hit by about 14,000 quakes every year, of which only a small number usually top a magnitude of 5.

Scientists had warned after the February quake that there would be further shakes, probably as large as magnitude 6.

In coming days the most likely scenario is that there'll be a series of aftershocks in a similar location and they'll gradually drop off, Ken Gledhill, a seismologist with GNS Science, told TVNZ.

This is just a reminder that this area is more active than it was in September 2010.

(Additional reporting by Gyles Beckford; Editing by Robert Birsel)