Tonga Met Services said at 3:30pm today Cyclone Ian is moving south-southeast at 8kt and on this track it affected the Ha'apai Group and expected to continue in the next few hours.
Tongan local media report said telephone communication to outer islands had been cut off.
The radio FM89.5 report said the sea surged inland ravaging the new Fire Station building and the Tokaikolo Church in Pangai.
One woman was reported to have been injured in the cyclone the radio said.
The radio said they have yet to confirm the information.
Radio & Television Tonga report said electric power restored to most part of Vava'u.
Tonga Met Services says, on its current track tropical cyclone Ian may bring very destructive hurricane force winds to the Ha'apai group from now until later today and damaging gale force winds to Vavau until later today.
For Tongatapu and ‘Eua the cyclone may bring damaging gale force winds in the next 6hrs..