A man has been arrested on suspicion of murder and attempted murder after a body was found next to a seriously injured girl.
The dead man was found in Dungannon, County Tyrone, the Police Service of Northern Ireland (PSNI) said.
The Northern Ireland Ambulance Service received an emergency call just after 11am on Saturday and took one patient to the Royal Belfast Hospital for sick children.
A terraced house has been sealed off at the scene in Lisnahull Road, with a number of officers and police cars in attendance.
A forensic officer was seen at the property with an evidence bag, and police have urged members of the public to avoid the area.
Sinn Fein councillor Deirdre Varsani said there was a "strong police presence" in the area.
She went on: "There appears to be a strong sense of shock and trauma and again we ask people to be respectful of the news that might be coming out, and if you have any information, even the smallest piece of information, to please pass that on to police."
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The PSNI said in a statement: "Detectives from the Police Service of Northern Ireland's major investigation team have launched a murder investigation after a man was found dead alongside a seriously injured child in the Lisnahull Road area of Dungannon this morning, Saturday, 29 August.
"A male has been arrested on suspicion of murder and attempted murder and remains in police custody at this time.
"A further update will follow in due course."
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