Police have confirmed a child has died and a woman and baby are in hospital after an incident at a farmhouse just outside Larne.
The PSNI confirmed it was investigating the death.
A spokeswoman said: "A woman in her 30s and a baby are currently receiving hospital treatment for injuries.
"The investigation is at an early stage and police are currently not looking for anyone else in connection with the death."
There was widespread shock in the rural community of Magheramorne on the outskirts of Larne after the emergency services descended on the isolated location on Monday morning.
One woman who knows the family said the mother is a nurse. She described the news as "shocking".
"You just wouldn't believe it," she told the Belfast Telegraph.
There remains a large scale police presence on the Bankhall Road area with neighbours saying they were "taken aback" with the scale of the operation.
One resident told the Belfast Telegraph the emergency services arrived in the area at around 10am.
She said police were focused on one farmhouse which had been sealed off. She said the air ambulance appeared to have airlifted at least one person to hospital.
Another neighbour said he was first alerted to the incident when he heard the sound of the helicopter overhead.
It is thought the residents are relatively new to the area, which has been described as a "quiet residential rural location". It is thought the family of four moved into the area around a year ago.
Another woman who lives on the road spoke to the Belfast Telegraph at the scene. She said the farmhouse has been rented out.
"I believe youngest child is a year and half and the eldest a bit older," she said.
She described the children as "beautiful and very young".
"I've spoken to the man once, but they generally keep themselves to themselves.
"You don't expect something like this to happen in a quiet area like this. You normally only read this in the papers."
She added: "I was heading into Larne at around 10am and was met by ambulance and police vehicles coming the other way. They then closed the lane off.