Waves roll through coastal Tongan homes after a tsunami warning was given for the whole Pacific islands nation.
"A 1.2 metre tsunami wave has been observed at Nukualofa," Australia's Bureau of Meteorology tweeted. The maximum tsunami wave recorded following Friday's explosion was 30 centimetres.
The latest eruption of the Hunga Tonga-Hunga Ha'apai volcano came just a few hours after Friday's tsunami warning was lifted.
It lasted at least eight minutes and sent plumes of gas, ash and smoke several kilometres into the air. Residents in coastal areas were urged to head for higher ground.
The eruption was so intense it was heard as "loud thunder sounds" in Fiji more than 800 kilometres (500 miles) away, officials in Suva said.
Victorina Kioa of the Tonga Public Service Commission said Friday that people should "keep away from areas of warning which are low-lying coastal areas, reefs and beaches."
The head of Tonga Geological Services Taaniela Kula urged people to stay indoors, wear a mask if they were outside and cover rainwater reservoirs and rainwater harvesting systems.
The Pacific Tsunami Warning Centre issued a "tsunami advisory" for American Samoa, saying there was a threat of "sea level fluctuations and strong ocean currents that could be a hazard along beaches."
The Hunga Tonga-Hunga Ha'apai volcano sits on an uninhabited island about 65 kilometres (40 miles) north of the Tongan capital Nuku'alofa.