A man suspected of killing his partner and her daughter was arrested at a country park after he was spotted by a member of the public with an injury, sources have said.
John Miller was held at Fairburn Ings Nature Reserve near Castleford after an altercation with paramedics who were trying to treat him.
They had been called after a member of public saw Miller struggling to walk and alerted the emergency services. Police were called after Miller's row with the paramedics and he was arrested.
Later police discovered the bodies of Miller's partner, Sarah Laycock, and her daughter Abigail at the family's home in Kirkby Avenue, Garforth, near Leeds. They also found a four-year-old girl with minor injuries.
A spokeswoman for West Yorkshire Police said: "Officers attended and following initial inquiries a house search was subsequently conducted at an address in Kirkby Avenue in Garforth in Leeds and a 31-year-old woman and an eight-year-old girl were found deceased in the property.
"A four-year-old girl was also found with minor injuries. She was taken to Leeds General Infirmary and later discharged.
"A 36-year-old man was arrested on suspicion of murder and attempted murder."
Kirkby Avenue remained sealed off on Sunday. Police could be seen standing outside the property and forensic officers wearing protective white suits could be seen at the side and rear of the property.
Neighbours spoke of their shock as news of the killings spread. Audrey Bottomley said: "I can't understand it. I was quite shocked when I heard.
Janet Hutchinson said she believed the girls were given bikes for Christmas, adding: "We are all shocked. You just don't know what is going on in other houses, do you?"