A 62-year-old woman was found dead with stab wounds at a home in north London on Wednesday.
The woman, who has not been identified, is believed to have known the 55-year-old woman who has been arrested on suspicion of murder.
Police had been called to a residential property on Westerham Avenue, Enfield, at 4.53pm on Wednesday.
She was pronounced dead at the scene when paramedics arrived.
Her family has been informed of her death, police said. A post-mortem examination of her body will take place in due course.
Detective Chief Inspector Sarah Lee said: Although we are in the very early stages of our investigation, I can confirm that we have arrested a 55-year-old woman on suspicion of murder. She is currently in custody.
I would like to reassure local people that we are not seeking anyone else in connection with this incident.
We believe that the victim and suspect were known to each other and there is no indication of any ongoing risk to public safety.
Detective Superintendent Marco Bardetti, leading local policing in Enfield and Haringey, said: I know that local people will be concerned by this shocking loss of life and there will be a heightened police presence in the area in the coming days to provide reassurance.
A crime scene remains in place, and I would like to thank local people for their patience while our specialist crime colleagues, supported by local officers, conduct their inquiries.
If you are concerned or worried, please do feel free to approach officers as they patrol or contact your local neighbourhood policing team.
Our thoughts are with the victims family at this sad time.
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