A distress signal has been detected in an isolated, low-lying group of islands in the Tonga archipelago following Saturday's massive volcanic eruption and tsunami, the United Nations said, prompting particular concern for its inhabitants.
Initial reports suggested no mass casualties on the main island of Tongatapu, but two people were reported missing and the capital Nuku'alofa was badly damaged, as were resorts and homes along the island's western beaches, it said.
"Further volcanic activity cannot be ruled out," the UN Office for the Coordination of Humanitarian Affairs (OCHA) said in the update on Monday, reporting only minor injuries but emphasising that formal assessments, especially of the outer islands, had yet to be released with communications badly hit.
The uninhabited volcanic island of Hunga Tonga-Hunga Ha'apai all but disappeared following the blast, according to satellite images from around 12 hours later. The Pacific archipelago was blanketed in ash and volcanic ash clouds spread to countries thousands of kilometres to the west.
The OCHA said there had been no contact from the Ha'apai group of islands and there was "particular concern" about two small low-lying islands - Fonoi and Mango, where an active distress beacon had been detected.
According to the Tonga government, 36 people live on Mango and 69 on Fonoi.
Experts said the volcano, which last erupted in 2014, had been puffing away for about a month before rising magma, superheated to around 1000 degrees Celsius, met with 20-degree seawater, causing an instantaneous and massive explosion.
The unusual "astounding" speed and force of the eruption indicated a greater force at play than simply magma meeting water, scientists said. [...]
