DUBLIN (AP) — Authorities say dozens of small sailboats taking part in a Northern Ireland regatta have capsized in stormy seas, triggering an emergency evacuation involving several lifeboats and a helicopter from the neighboring Republic of Ireland.

Northern Ireland coast guard and lifeboat officials say about 10 people have been treated for hypothermia after their two-member sailboats tipped over in Strangford Lough. They say nobody has been reported missing.

Monday’s trouble came during the first competitive race of a planned week-long regatta in the lough, an almost totally landlocked inlet southeast of Belfast.

Four of the 14-foot (4-meter) dinghies capsized during a practice run Sunday because of high winds and waves driven by the remnants of Hurricane Bertha, which arrived in Britain and Ireland over the weekend.

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