The shake-up was followed by four relatively minor tremors, between 2.3 and 3.3 magnitude, all 5km southeast of Pōrangahau, says GeoNet.
Another 4.8-magnitude quake struck at midnight, 10km southeast of Pōrangahau, reportedly at a depth of 18km.
A total of 1438 people reported feeling that earthquake.
Another trio of relatively smaller shakes followed.
The first was a 2.2-magnitude earthquake 5km east of Pōrangahau at 2am, followed by a 2.3-magnitude earthquake 5km southeast of Pōrangahau at 3.53am, and a 2.1-magnitude earthquake in the same location at 9.23am.
GeoNet recorded the shaking as “strong” for both 4.8-magnitude events, however, the most of the self-reports to the website were “weak” or “light”.
Few reported feeling the smaller earthquakes in between.
People up and down the North Island reported feeling the quakes, as well as some in the middle of the South Island.
