7.1 magnitude earthquake hits New Zealand, tsunami alert issued

Authorities say the region experienced a swarm of aftershocks, several of nearly 6.0 magnitude, for many hours

A massive earthquake of 7.1 magnitude struck off the east coast of New Zealand on Friday early morning triggering a small tsunami. However, the officials said there were no reports of significant damage or injuries.

The US Geological Survey said the tremor hit at 4:37am at an estimated depth of around 30 kilometres (18 miles). It was centred 167 kilometres (103 miles) from the nearest main town, Gisborne, which has a population of around 45,000.

The region experienced a swarm of aftershocks, several of nearly 6.0 magnitude, for many hours after the initial jolt as coastal residents made their way to high ground by torchlight.

Within three hours, a 30-centimetre (one foot) tsunami was detected and the authorities issued a warning. The tsunami warning covered the East Coast of the North Island and the upper South Island.

"The greatest wave height has already occurred, further waves are anticipated to be up to 20 centimetres," the Civil Defence organisation, which is responsible for national emergency management told AFP.

The organisation added: "Areas under 'marine and beach threat' can expect unusually strong currents and unpredictable water flows near the shore. This means a threat to beach, harbour, estuary and small boat activities."

Sheridan Gundry, the East Coast Civil Defence information officer said that the impact was minimal.

"We haven't heard any reports of injuries or damage at all," she told Radio New Zealand.

"There was power out in a few places but we've been let off pretty lightly as far as damage goes," she added.

New Zealand is located on the boundary of the Australian and Pacific tectonic plates, which is a part of the "Pacific Ring of Fire", and hence it experiences up to 15,000 tremors a year.