An eight-year old boy has died and his father is fighting for his life after they were overcome by slurry fumes on a Co Antrim farm.
The 52-year-old father Robert Christie and his son, also called Robert, were working on a farm on Ballynaloob Road near Dunloy when the accident happened.
Both were overcome by poisonous fumes as they were mixing slurry and it is understood they were found by a postman on Saturday afternoon.
The boy was airlifted to hospital in Belfast, but doctors were unable to resuscitate him.
Mr Christie remains critically ill in the Royal Victoria Hospital in Belfast.
Ballymoney mayor John Finlay said: "There has been a tragic farm accident and I would like to say that the family are in my thoughts.
"The whole of the community here has been calling me to voice their concern for the family."
The man and his son are thought to have been spreading slurry when the accident took place.
A spokesman for the Police Service of Northern Ireland (PSNI) said: "Police can confirm that the Health and Safety Executive are currently conducting an investigation into the circumstances surrounding a farming accident in Dunloy on Saturday, June 7.
"At the request of family members police will not be releasing any further details at this time."
It is the latest in a long line of fatal accidents involving slurry tanks on Northern Ireland's farms.
In September 2012, up and coming Ulster rugby star Nevin Spence, his father Noel and brother Graham died after entering a slurry tank.
The tragedy happened after Graham, 30, went into the tank in an attempt to rescue a dog at the family's farm outside Hillsborough, Co Down.
Nevin, 22, went in to assist his brother but also lost consciousness before 58-year-old Noel was killed trying to save his sons.