A 4.2 magnitude earthquake struck south of Hastings in the early hours of this morning.
The quake had a depth of 73 kilometres and was centred 35 km east of Porangahau in the Pacific Ocean.
GNS said the intensity of the earthquake, which hit at 1.06am, was weak.
Felt reports on the agency's website showed 23 people across the south-east of the North Island, and as far south as Argyll in the South Island, shook when the quake struck.
Meanwhile, a 3.3 magnitude quake hit 30 km south-west of New Plymouth shortly after midnight.
