A shallow, powerful earthquake has struck off the northeastern coast of New Zealand, with officials warning of a possible tsunami threat.
There are no immediate reports of serious damage or casualties.
The U.S. Geological Survey said the quake measured a preliminary 6.9 magnitude and was centered at a depth of 10 kilometers about 178 kilometers northeast of the city of Gisborne. It said residents of Gisborne reported light to moderate shaking.
New Zealand's National Emergency Management Agency said it was still assessing whether the quake had triggered a tsunami that could affect the country.
A magnitude 6.3 quake in 2011 hit the city of Christchurch, killing 185 people and destroying much of its downtown.
