Wellington, Dhu-AlQa'dah 29, 1437, September 01, 2016, SPA -- A tsunami warning has been issued for parts of New Zealand following a powerful 7.1-magnitude earthquake early Friday, emergency officials said, according to dpa. The quake struck at 4:38 am (1638 GMT Thursday) at a depth of 19 kilometres, the US Geological Survey said. It was centred off the north-eastern coast of the North Island, some 166 kilometres from the city of Gisborne. A series of strong aftershocks following shortly after. The east coast of the North Island - including the city of Auckland - and Upper South Island are under a tsunami warning, the New Zealand Ministry of Civil Defence and Emergency Management said on Twitter. "Tsunami activity will continue for several hours and the threat must be regarded as real until this warning is cancelled," the agency wrote, urging people to stay away from coastal areas. --SPA 22:16 LOCAL TIME 19:16 GMT www.spa.gov.sa/w