Police say the woman in her 60s died in the Greenhill area of Sheffield on Wednesday night.
A 12-year-old boy has been arrested on suspicion of murder after a woman was struck and killed by a car in Sheffield.
The woman in her 60s died at the scene after being found seriously injured in the Greenhill area of the city at about 19:10 BST on Wednesday, police said.
The boy was found a short time later and arrested.
He was also arrested on suspicion of possession of a bladed article, South Yorkshire Police said.
The suspect remained in custody on Thursday, the force added.
Yorkshire Ambulance Service and South Yorkshire Fire and Rescue Service also attended the scene, police said.
Det Ch Insp Andrea Bowell, from South Yorkshire Police, said: “This will be a deeply distressing time for the families of those involved in this incident, and I would ask their privacy is respected as they seek to understand what has happened.”
Anybody with information is asked to get in touch with police, or via Crimestoppers.
At the scene: Oli Constable
Half a dozen bouquets of flowers have been placed on Hemper Lane this afternoon.
A steady stream of people have been walking past a police officer standing guard at a small cordon outside a house on the street.
However, other than the police cars which are coming and going from the scene, the road is quiet.
A lot of people I’ve spoken to here don’t want to talk about what happened.
But knowing that a woman died in their street last night, the community is clearly shocked.
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