Videos captured scenes of fear and chaos as a man clad in body armour and armed with two crossbows, a sword and a knife burst into a property in south London before being shot dead by police.
The Metropolitan police said they were called by people inside the home at 4.55am to reports of a man trying to break in, at Bywater Place, Southwark.
The man in his 30s was threatening harm to those inside.
Investigators are examining the nature of the relationship between the man and those inside the property. The man shot dead was known to at least one of the occupants at the address, the Independent Office for Police Conduct (IOPC) said.
The police watchdog is investigating the shooting and said an arsenal of weapons had been recovered from the scene, including crossbows, a knife, a sword and a hatchet.
The man who burst into the home was wearing body armour, the police watchdog added.
Video from the scene examined by the Guardian captures the voice of a woman in distress, repeatedly shouting “please”, and at other times banging can be heard.
The Met said its local unarmed officers tried to calm the man down but were threatened, with the man getting inside the home.
At that point an armed officer from an armed response vehicle that had been called in decided to open fire, and the man was shot twice. The man was pronounced dead at the scene and police say two people inside the house received minor injuries.
Audio from the video records a male voice shouting “armed police” and shortly after the same voice saying: “Everyone inside the address come to the door with your hands on show.”
Assistant commissioner Matt Twist, who has overall responsibility for firearms for the Met, said: “Armed officers were called and attempted to get the man to surrender. They entered the property and shots were fired.
“The officers, assisted by paramedics, provided emergency first aid to the man, who was wearing body armour, but he sadly died.
“Weapons recovered from the scene include crossbows, a knife, a sword and a hatchet.
“This is an extremely difficult day for everyone involved. I would like to pay tribute to the bravery of all our officers who responded and thank all the emergency service staff involved.
“I firmly believe their actions prevented further loss of life.”
Earlier video captures an officer at the scene radioing the police control room to say a man had forced his way inside, armed with a crossbow and possibly a sword. There are further shouts from police to “withdraw” and of “containment”.
Neighbours said they had heard repeated banging, shouting and a woman screaming at about 5am, before hearing police sirens and gunshots.
They described the area as usually peaceful. Maisie Cooper, 24, said: “It’s a bit scary and weird. Nothing like that ever happens here.”
Most neighbours said they did not know who lived at the property. One said he believed only adults lived there. He thought there was one woman and two men, all in their 20s, whom he had seen socialising on their back patio.
In front of the property, a white and yellow tent could be seen with a pile of items scattered on the ground. In drone footage of the site, these appeared to include a gas mask and body protection.
The cul-de-sac was closed off with a police cordon, where forensic officers in blue overalls were visible.
Akber Baloch, 52, a restaurant owner, said: “I was sleeping and I heard some shouting. It was also like someone was banging a door. There was banging and shouting. It sounded like a man and a woman.”
All fatal police shootings must by law be investigated by the IOPC. Police are allowed to use force to defend themselves or others but it must be proportionate to the threat.
DCS Seb Adjei-Addoh, who leads policing in Southwark, said: “My thoughts are with all those affected by this incident. I understand the local community will be concerned at the events that have taken place this morning. We will fully support the IOPC investigation into the full circumstances of what happened.”
Mel Palmer, an IOPC regional director, said: “Given a man has died after being shot by police, our role is to independently investigate all of the circumstances surrounding this incident including the actions and decisions taken by the police.
“We appreciate that the community will want answers quickly and our investigators are working hard to establish the facts and piece together what occurred.”
British police are largely unarmed, but can call in officers with guns if the situation is thought to be dangerous enough to merit an armed response.
A fleet of armed response vehicles patrol the capital, usually containing three armed officers. The Met says armed officers carry out an average of 4,800 deployments a year, and over the last 20 years opened fire on average two times a year or less.