A man in his twenties has died after a tree fell on him as he worked in Slieve Gullion Forest Park in Co Down.
A second man, aged in his forties, has been taken to hospital following the accident which happened as Storm Ali battered Ireland.
It is understood the men were contractors for Northern Ireland Water.
The PSNI said the death is being investigated by the Health and Safety Executive and there were no suspicious circumstances.
"Police attended the sudden death of a man, aged in his 20s, in the Slieve Gullion Park, Drumintee Road area of Newry this afternoon," a police spokeswoman said.
The death comes after a woman in her fifties was killed when a caravan was swept off a cliff in Co Galway. The caravan was blown onto a beach at Claddaghduff, near Clifden in Co Galway, this morning.
By 5pm more than 170,000 customers across the island were still without power.
- Storm Ali updates
STORM ALI UPDATE: 5pm. So far today we have restored power to 60,000+ customers. Our crews continue to restore power to the remaining 126,000 affected customers, however those impacted by outages should prepare to be without electricity for up to 3 days.https://t.co/98bzds4OQZ pic.twitter.com/6O6iWjWBPx
— ESB Networks (@ESBNetworks) September 19, 2018