The ambulance service responding to the incident in Strangford Lough has said that some people are suffering from hypothermia, UTV reporter Aidan Kennedy has tweeted:
BREAKING NEWS - AMBULANCE SERVICE SAYS A NUMBER OF PEOPLE WITH HYPOTHERMIA AFTER 100 PEOPLE FEEL INTO WATER DURING KILLYLEAGH BOAT RACE
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Cooler and fresher across the UK over the next few days.
The prime minister was shouted at as she left the scene of the tragedy in which at least 79 people died.
Father-of-six Makram Ali, 51, was already receiving medical treatment as the attack unfolded. He died from multiple injuries, police say.