A toddler has died and another child and a woman have sustained serious injuries during an incident at a house outside Larne in Co Antrim.
Police are believed to be treating the situation at a rural farmhouse on the Bankhall Road in Magheramorne as a domestic incident.
They have confirmed they are not looking for anyone else in connection with the child's death.
It is understood the woman, who is in her 30s, and a baby are being cared for in hospital with suspected stab wounds.
The scene is cordoned off this afternoon.
Police and other emergency services attended the incident.
The PSNI said in a statement: "Police can confirm that an investigation has commenced into the circumstances surrounding the death of a young child in the Larne area today.
"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."