A man, believed to be in his 20s, and a woman in her 80s have been attacked in Brentford.
A man has been killed and a woman in her 80s is in a critical condition in hospital following a double stabbing in west London.
Police found the man, believed to be in his 20s, with stab wounds in Albany Parade, Brentford at about 20:00 GMT on Friday.
Despite emergency treatment, he was pronounced dead at the scene.
A injured woman was taken to hospital where she remains in a critical condition. Police have made no arrests.
A spokesman for the Met Police said inquiries were ongoing to establish the identity of the dead man.