A man has died and a woman is in a critical condition after being stabbed in Brentford, west London.
Police said there is nothing to suggest the incident is linked to terrorism. No arrests have been made.
A man aged around 20 was pronounced dead at the scene in Albany Parade at about 8pm.
Scotland Yard said officers are trying to establish his identity and “his family have not yet been informed”.
A post-mortem examination will be arranged.
The woman, aged in her 80s, was taken to hospital and is said to be in a critical condition.
London Ambulance Service said it was called at 7.49pm on Friday.
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It added: “We sent a number of resources, including four ambulance crews, a medic in a car, a clinical team leader, an incident response officer, a hazardous area response team, and an advanced paramedic. We also dispatched by road London’s Air Ambulance.
“Sadly, one person died at the scene. We treated another person at the scene and took them to a hospital as a priority.”
Anyone with information is asked to call 101, mentioning reference 6423/12NOV.