Initially, seismologists reported about a 6.2 magnitude earthquake.
The quake was registered at 09:41 GMT about 60 miles to the east from Hihifo town at the depth of 6.2 miles.
No casualties or destruction have been reported. USGS noted the "green level" of the threat of the quake consequences, indicating a low probability of casualties and economic damage.
The Kingdom of Tonga and New Zealand are located in a seismically active zone known as the Ring of Fire and regularly suffer from powerful earthquakes.