A fisherman has died in hospital after being overcome by fumes while working on a trawler.
The fisherman, named as James Joyce (27) from Pump Rd, Inis More in the Aran Islands, died on Monday night in Letterkenny General Hospital.
He had been placed in an induced coma earlier in the day.
Another fisherman overcome by fumes in the same incident, a 46-year-old from the Philipinnes, remains in a critical condition in the intensive care unit in Letterkenny.
The men were overcome by fumes on Monday afternoon on the Galway-registered Oilean an Oir in Killybegs, Co Donegal.
They were cleaning tanks in a refrigeration unit when the Galway man fell into the hold. The Filipino was overcome with fumes when he tried to aid him after calling for help from other crew-members.
The incident is being investigated by officers from the Marine Casualty Investigation Board. One theory is that fumes from stagnant water may have played a role.
Local Independent Donegal county councillor Niamh Kennedy, who visited the scene, said: “It’s not unusual for stagnant water to occur in vessels”.
She said decaying matter could create ammonia and hydrogen sulphide, which could be a deadly combination.
"When you have stagnant water lying in the hold of a ship for a while, or any confined space, you will find that this thing happens." She said the fishing community of Killybegs offered its sympathy to Mr Joyce's family and to the crew of the Oilean an Oir, and they were praying the injured man survived.