A murder inquiry has been launched into the death of a woman who was found injured by paramedics called to a block of flats in Derbyshire.
The victim, believed to be aged 27, was taken to Nottingham's Queen's Medical Centre from an address in Ilkeston.
Police said the woman, who has yet to be named, died in hospital shortly after her arrival.
A police spokesman said: "Officers were called to a small complex of flats on Critchley Street in Ilkeston, where they found paramedics treating a woman for injuries.
"A 48-year-old man was arrested at the scene and remains in police custody.
"The woman's family have been informed of her death but she has not been formally identified."
An incident room has been set up and a Home Office pathologist is due to carry out a post-mortem examination to determine the cause of death.
Anyone with information that would help the police inquiry is urged to contact Derbyshire Police on 101.