Cyclone Gita has been upgraded to a category five storm after battering parts of southern Fiji.
Residents on low-lying islands said several homes were flattened and crops were wiped out when the cyclone pounded their villages.
"We were afraid, we were terrified," Noah Sukanasau told the ABC's Pacific Beat program.
"We have lost all our food, our plantation. We have lost our houses and our property.
"The good news is everyone is safe and no-one was injured."
Mr Sukanasau said many people had been taken to evacuation centres.
"This is the strongest hurricane I have faced. I am 68 years, and this is the strongest hurricane I have felt," he said.
"Three houses were blown right to the ground here in my village."
Fiji escaped a direct hit but emergency authorities remain concerned for thousands of people on islands in the southern Lau group, where communications have been cut.
The remote Ono-i-Lau islands faced wind gusts of up to 190 kilometres per hour as the storm passed on Tuesday afternoon.
Emergency authorities said they were confident they would be able to quickly provide the required assistance.
"As we speak our Government is making the necessary plans for the response," director of Fiji's National Disaster Management Office Anare Leweniqila said.
Forecasters said the cyclone was moving away from major land areas for now but was headed towards Vanuatu's most southern islands and New Caledonia.
"It is expected to remain a category five system for the next 24 hours," forecaster Rajnell Prasad said on Wednesday morning.
"We expect the system to gain in speed and move in the west-south-west direction."
Australian, New Zealand aid sent to Tonga
On Tuesday, the storm caused major structural damage across Tonga, and the clean-up there is only just beginning.
The Parliament building in Nuku'alofa was among those flattened as the cyclone lashed the main island of Tongatapu.
Australia and New Zealand have flown emergency aid supplies to Tonga.
"A Defence Force plane — a C-17A Globemaster — is departing with humanitarian assistance and will reach Tonga this evening," Minister for International Development and the Pacific, Concetta Fierravanti-Wells told Pacific Beat on Tuesday.
"We are sending life-saving equipment, emergency shelter, kitchen and hygiene kits."