The first aircraft carrying humanitarian supplies has arrived in Tonga, five days after the South Pacific island nation was hit by a volcanic eruption and tsunami that devastated communities and spoiled most of its drinking water.

The explosion of the Hunga Tonga-Hunga Ha’apai volcano on Saturday killed at least three people, sent tsunami waves rolling across the archipelago, damaging villages, resorts and many buildings, and knocked out communications for the nation of about 105,000 people.

Telephone links between Tonga and the outside world were reconnected late on Wednesday, though restoring full internet services was likely to take a month or more, according to the owner of the archipelago’s sole subsea communications cable.

The United Nations said that about 84,000 people – more than 80 percent of the population – has been badly affected by the disaster with safe water being “the biggest life-saving issue”.