A man was being questioned on Saturday night about the murder of a teenage girl and the serious wounding of her sister in a gun attack in a small village in Northern Ireland.
Police are examining the scene at a house at William Court in Bellaghy, near Magherafelt, Co Derry, for clues to the incident which has stunned the community.
The dead girl was 18 and had celebrated her birthday within the last two weeks.
Her older sister, aged 21, lived at the rented house, in a recently built development at the back of the established housing estate.
Locals said the seriously injured woman is a mother of two young children.
It is believed she has been taken to the Royal Victoria Hospital in Belfast for surgery.
A 26-year-old man was arrested on suspicion of murder around half an hour after the shooting, the PSNI said.
Another man and a woman, both aged 28, were arrested on suspicion of assisting an offender.
All three were detained in Toome, about five miles away from the scene of the gun attack.
It is understood the dead girl had been living at her family home, in a neighbouring housing estate, and was visiting her older sister at the time of the shooting.
Locals reported seeing and speaking with her in the village during the morning, before police were called to the scene at around 10.40am.
Martin McGuinness, Northern Ireland's deputy first minister and Mid-Ulster MP, said his heart went out to the family of the girl tragically killed.
"People I have spoken to in the area this morning are in a state of shock," he said.
"I would wish to extend my thoughts and prayers to the family and friends of the victim at this terrible time."
A PSNI spokesman said they were alerted to the shooting shortly before 10.40am on Saturday.
Forensic police at the scene of a shooting at William Court in Bellaghy
He added: "At around 11.10am, a 26-year-old man was arrested on suspicion of murder and a 28-year-old male and 28-year-old female were arrested on suspicion of assisting an offender.
"All three were arrested in the Toome area and have been taken to the Serious Crime Suite at Antrim police station."
Investigating officers have appealed for anyone with information about the incident to contact them.
Caoimhe Scullion, Sinn Fein councillor on Magherafelt District Council who lives in Bellaghy, said the tight-knit village had been plunged into shock over the gun attack.
"Everybody is in complete shock," she said.
"We hear these stories happening everywhere else, but you never think it will happen on your doorstep."
Ms Scullion said everybody knows everybody else in the small village.
Ian Milne, also a Sinn Fein councillor who lives in Bellaghy, said the dead girl marked her 18th birthday within the last two weeks.
"The area is in total shock," he said.
"Nobody can understand why this has happened. Everyone is very raw."
Mr Milne added: "Our thoughts and prayers are with the family. We hope and pray the girl that is injured will make a recovery."
The scene remained sealed off and was being examined by forensic experts.
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