Tonga reports widespread damage and one death from Cyclone Ian

One person is dead in Tonga after Cyclone Ian ripped through the Pacific Island nation.

The category-five storm hit on Saturday, and there have been reports of flattened houses, felled trees and fallen power lines.

Tonga Red Cross head Sione Taumoefolau said one person died on Lifuka, an area believed to have been devastated, Matangi Tonga news website reported on Sunday.

The extent of the damage was not clear, but the islands of Ha'ano and Foa were also believed to be badly affected.

New Zealand Foreign Affairs Minister Murray McCully said his country had sent a RNZAF P3 Orion aircraft, which arrived in Tonga on Sunday morning to assist with aerial assessments.

``We will also make $NZ50,000 ($A46,900) immediately available to respond to specific requests for assistance,'' he said.

Mr McCully said further support would be considered when the full extent of the damage was clear.

He said early reports suggested damage to buildings in Ha'apai, limited communications and power outages.

``Our thoughts are with the people of Tonga as they begin to come to terms with the damage caused by this cyclone,'' Mr McCully said.

Strong winds ripped from houses and public buildings have been damaged in the South Pacific nation after Cyclone Ian crossed over the archipellago today.

Telephone communications with the Ha'apai island group were cut as the storm reached its height, but local news media cites radio reports of a sea-surge on the island of Pangai which damaged the island's new fire station and the Tokaikolo Church.

Tonga's director of emergencies, Leveni Aho, had earlier cited reports of roofs ripped from homes and some major buildings - including three churches - as it moved through the Ha'apai groups of islands.

"This is one of the strongest cyclones on record in the last 50 years. We are concerned for the welfare of many people and the threats involved," he said.

The extent of the damage was still being assessed, but the destruction appeared to be less extensive than Tongans had feared from the first category-five storm they had experienced in decades.

``The lucky part ... is that although it is very highly dangerous, the eye was so narrow, the extent of the damage is not what you associate normally with a category-five cyclone,'' Aho said. He estimated the storm's eye was less than 60 kms (35 miles) across.

A state of emergency was declared for two of Tonga's three island groups, Vava'u and Ha'apai, on Saturday morning as category-five storm Cyclone Ian brought heavy rain and strong winds forecast to gust at up to 287 kilometers per hour, the Matangi Tonga news website said.

A United Nations humanitarian relief agency reported that a wharf in the main town of Neiafu had been washed away. Police and military are checking and clearing roads, it said, and power supplies which were cut by authorities before the cyclone struck but have now been restored.

The storm was downgraded to category four, with gusts of up to 250km/h, but later reclassified as category five, the most severe rating.

It bypassed Tongatapu, the most populated island, which escaped damage.

Oxfam New Zealand executive director Barry Coates said the organisation was preparing to send staff to Tonga within 48 hours to identify the most urgent needs for people.`We have received a damage report from the island of Hunga and our team are still out trying to get a feel, but there doesn't appear to have been much damage in Vava'u at the moment,'' Tonga's Director of Emergencies Leveni Aho told the website.

Aho advised against travel between Tongan islands during the storm and urged residents of outer islands to stay put.

Aho said the decision to declare a state of emergency was made as initial reports of damage began coming in.

"It means we have the national resources ready to deploy in areas of need and authorities are given power to evacuate if needed," he told the Matangi Tonga news website

 New Zealand's Ministry of Foreign Affairs and Trade says there are 114 Kiwis registered in Tonga and are urging those who haven't yet registered to do so.

The ministry says the Tongan government has not yet officially asked for assistance, however New Zealand "stands ready to assist if requested".

"The Ministry of Foreign Affairs and Trade is monitoring the path of Tropical Cyclone Ian closely," a ministry spokeswoman said this afternoon.

"The cyclone is currently still passing over the islands of Tonga."

On its current track it is expected to impact parts of Tonga until early Sunday morning.

Unicef NZ executive director Dennis McKinlay said it was ready to send relief supplies if needed.

"We have pre-positioned supplies in Suva for emergencies, but until the cyclone has gone through and we know what the needs of the people are and what damage has been done, it's too soon to take any action yet,'' he said.

"Exactly the path of it is not quite known and it's shifted and changed quite a bit. It's a little bit hard at the moment.''

The worst of the storm is forecast to hit tonight.

Tonga is an archipelago of 176 islands, 36 of which are inhabited by more than 100,000 people.