It is believed the man arrested and all four of the victims knew each other.
A man has been arrested following the deaths of four people in London on Monday (25 April).
Metropolitan Police were called at about 1.40am to reports of a disturbance at a residential address on Delaford Road in Southwark.
Police forced entry into the property, and discovered four people suffering what are believed to be stab wounds.
All four people, three women and a man, were pronounced dead at the scene.
A man has been arrested on suspicion of murder, and is currently in a south London police station where he remains in custody.
It is thought that all five people involved were known to each other.
Next of kin are in the process of being contacted, and post mortem examinations are set to be arranged.
Detectives from Specialist Crime are investigating, and enquiries continue to establish the circumstances.
