NUKU'ALOFA, Tonga (AP) -- Authorities were searching remote islands for cyclone victims on Sunday after the most powerful storm to hit Tonga in decades cut a swathe of destruction through this South Pacific archipelago, leaving at least one person dead and several injured.
Relief efforts following Saturday's storm were concentrating on the Ha'apai islands -- one of Tonga's three island groups between the main island of Tongatapu in the south and the Vava'u islands to the north, Tonga's Director of Emergencies Leveni Aho said.
Cyclone Ian hit Tonga with gusts up to 287 kilometers (178 miles) per hour. The storm was later downgraded from the top of five-scale destructive cyclones to category four, with gusts of up to 250 kph (155 mph). On Sunday, the cyclone was tracking southeast away from Tonga.
Two navy patrol boats carrying tarpaulins, tents and other emergency supplies left Tongatapu to bring help to victims who were cut off in the Ha'apai islands.
Aho said authorities have been unable to make telephone contact with 23 islands, which account for most of the inhabited islands in the Ha'apai group.
"The patrol boats are still out there, going from island to island to scout for information," Aho said.
Ha'apai islands are home to 8,000 people, most of whom live on the devastated islands of Lifuka, where one person died, and Foa.
Aho estimated that hundreds of people on the two islands were taking shelter in church buildings that were being used as evacuation centers.
A New Zealand air force P3 Orion plane made a surveillance flight over the disaster area on Sunday, taking pictures showing the extend of the damage that surprised officials.
Aho said up to 70 percent of the homes and buildings in some areas had been flattened.
"There is much more damage on the ground that we anticipated before," he said.
"At this point, there's only one fatality. There are some injured, but that is still manageable with the existing medical facilities there," he added.
He said there were no reports of survivors with life-threatening injuries.
Tongan authorities would further assess the damage before they would consider asking for international help, Aho said.
Aho said that storm damage to the Tongatapu and Vava'u island groups was slight.
Weather was fine Sunday, but rough seas were hampering the patrol boats' relief mission, he said.
Tonga is an archipelago of 176 islands, 36 of which are inhabited by more than 100,000 people. Its economy relies on fish export, tourism and remittances from Tongan communities overseas, with about 40 percent of the population living in poverty.
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