This is the moment the water level in a coastal area in Fiji rose after an undersea volcano in Tonga erupted and triggered tsunami warnings across the South Pacific on Saturday January 15.

Footage shows the tide slowly swelling and encroaching on the shore in Fiji on Saturday afternoon, moments after the huge undersea explosion occurred.

Tonga’s Hunga-Tonga-Hunga-Ha’apai volcano erupted on Saturday in a powerful blast reportedly comparable to the cataclysmic eruption of Mount Pinatubo in the Philippines 30 years ago.

The extent of the damage is still unknown as clouds of volcanic ash has hampered aerial surveillance efforts, and communication lines are still severed across a large swath of Tonga, which has a population of about 105,000 people.

Tonga Parliament Speaker Lord Fakafanua said: ‘Communications remain down and the full extent of the harm to lives and property is currently unknown.

‘What we do know is that Tonga needs immediate assistance to provide its citizens with fresh drinking water and food.’