Police are investigating after three women and a man were stabbed to death in a brutal attack on Monday.
A suspect aged in his 20s, who is known to the victims, is currently being questioned under suspicion of the murders that took place at the family's €700,000 home in South East London.
The victims' identities have been revealed as grandmother Dolet Hill, 64, her partner Denton Burke, her daughter Tanysha Drummonds, and her granddaughter Samantha Drummonds.
READ MORE: Infamous Real IRA killer Robert Duffy granted day out of prison for driving theory test
Police rushed to the scene at around 1.40am after receiving reports of a disturbance at the home. One witness claimed that a group of armed officers ran into the home.
Inside, police found four people believed to have been stabbed to death, the Met said.
Despite the efforts of emergency services, all four were pronounced dead at the scene, Scotland Yard said in a statement.
Speaking from the scene yesterday afternoon, Metropolitan Police Commander Colin Wingrove said: "In the early hours of this morning, following a call from neighbours, officers forced entry into a house.
"Inside the house, they made a dreadful discovery of four people who had been stabbed. All four people were sadly announced dead at the scene.
"A man in his late 20s was arrested at the address on suspicion of murder, and he is currently in custody. At this early stage, we are not looking for any other person. We believe all those involved may have been known to each other.
"I want to offer my heartfelt condolences to the family and friends of all those concerned.
"This is a deeply shocking incident, and we will do everything we can to provide support to everyone affected at this difficult time."
A large police presence remained at the scene throughout the day, where a large barrier was erected to block the road, and several forensic tents were in place.
Four body bags were loaded into private ambulances following the discovery of the bodies.
One man told The Mirror what his son, 15, saw in the early hours of Monday.
"He could see four police getting out of a 4x4 fully armed with machine guns," the dad explained.
"He thought they had shot someone, and they were giving treatment for that by an ambulance. But obviously, this morning, we hear they've been stabbed.
"He was woken up by the police arriving and looked out of the window, and, in his tired state, saw four people were lying in the street outside getting CPR. I don't know exactly if that's how it happened."
A neighbour who didn't want to be named said: "I was watching telly when about half one in the morning, I heard a woman screaming for about five minutes.
"It was awful. But when I heard the police, the helicopter, the ambulances, I knew it was really serious.
"I saw about eight or nine police cars - all were armed - come out and surround the area."
A spokesperson for London Ambulance Service said four people died at the scene and that one man was taken to hospital "as a priority".
They would not confirm whether the person hospitalised was the same one as the man arrested but did say only five people were found in the house.
Get breaking news to your inbox by signing up to our newsletter .
