stabbing
The incident is the fourth fatal knifing in south London in five days.
Two people have been stabbed and one person has been arrested at the Sony Music building on Derry Street, Kensington in London.
A cordon remains in place.
Another man was injured in a separate shooting.
20-year-old to be questioned further once discharged from hospital.
An 18-year-old man was also hurt.
Three arrested on suspicion of murder released under investigation.
The 74th murder investigation in the capital this year has been launched.
A 48-year-old woman has been arrested.
An injured 48-year-old woman was also found at the same address.