The Royal New Zealand Navy dispatched two ships to Tonga Tuesday, but New Zealand’s minister of defense said it would take three days for them to reach the Polynesian archipelago nation, CNN reported.

Tonga was struck by a tsunami and covered with ash after an undersea volcano erupted 40 miles south of the capital city Saturday. Two people died in Tonga, and two others drowned in Peru after high waves caused by the eruption reached that country’s coast.  

The HMNZS Wellington and HMNZS Aotearoa left New Zealand for Tonga Tuesday, a journey of over 1,400 miles. The ships carry a rescue helicopter, disaster relief supplies, and a desalination plant to produce fresh water. Much of the fresh water on Tonga’s low-lying islands has been contaminated by saltwater flooding and falling ash.

The New York Times warned that aid workers also risked introducing COVID to Tonga, which has so far been almost entirely free of the virus. The country’s only confirmed case to date was detected in an air traveler from New Zealand in October, NPR reported. According to the World Health Organization, over 137,000 COVID vaccine doses have been administered to Tonga’s population of around 100,000.

Communications with Tonga are still spotty because of damage to the submarine cable that connects the archipelago to the outside world, but aerial surveillance photos show entire islands covered in monochromatic blankets of ash.

According to CNN, repairs to the cable not expected to begin until February.