Detectives have launched a murder investigation after a 25-year-old woman died after being repeatedly stabbed.
A 22-year-old man was arrested at the scene on suspicion of murder and remains in custody.
A Met Police spokesman said detectives "are not looking for anyone else in relation to the investigation."
Police were called to a home in Pinkwell Lane, Hillingdon after reports of a woman with multiple stab wounds.
Emergency services, ingluding the air ambulance, were called at about 5am yesterday but she was pronounced dead less than two hours later.
The woman's next of kin have been informed but she has not yet been formally identified.
A post-mortem examination started yesterday at Uxbridge Mortuary.