Alfie Stone killing: Three arrested on suspicion of murder
Three people have been arrested on suspicion of the murder of an 18-year-old man near a west London Underground station.
Alfie Stone died in hospital after being stabbed in the chest near West Ruislip Tube station during Monday's rush hour.
A 28-year-old man and two women, aged 29 and 32, were held on Wednesday. They remain in custody.
Another man, aged 27, was arrested on Monday and has been released on bail.
The victim, who lived in north-west London, was the 13th teenager to die from a stabbing in London this year.
The assault took place in High Road, Ickenham, at about 17:30 GMT.