MOSCOW (Sputnik) — The quake hit 103 miles from the city of Gisborne in the North Island at 16:37 GMT. It lied at the depth of almost 12 miles.
"We have issued a Tsunami Potential Threat advisory in all New Zealand coastal areas including the Chatham Islands," the ministry said in a statement.
It warned residents in coastal areas to keep off beaches due to possible strong tsunami currents and surges, and urged the population to follow instructions of their local civil defense authorities.
"Tsunami activity will continue for several hours and the threat must be regarded as real until this warning is cancelled," the ministry said on Twitter.
The US National Weather Service Pacific Warning Center said earlier there was no tsunami threat. It measured the wave caused by the quake at slightly over 8 inches.
