Crossbows, a knife, a sword and a hatchet were found in a house where a man was shot dead by police in south London.
Police were called to the address in Bywater Place, Surrey Quays, just before 5am on Tuesday.
A 30-year-old man was trying to force his way into a building and was threatening to hurt people inside, police said.
Unarmed officers tried to speak to him but were threatened, and when police marksmen arrived he had got into the building and was shot.
The man, who was wearing body armour, was given first aid but died at the scene.
Investigators from the Independent Office for Police Conduct (IPOC) watchdog have been at the scene throughout the day.
The dead man was known to at least one of the occupants of the address, the watchdog said.
It also said police body-worn footage confirmed he was trying to threaten people at the address.
Two shots were fired from a police issue firearm, which will be subject to further analysis.
An IPOC spokesperson said: “Among the weapons found at the scene were crossbows, a knife, a sword and a hatchet.
“A detailed search of the scene is continuing this evening and we have conducted house-to-house inquiries in the neighbourhood, which will continue in the coming days.”
Two people in the building suffered minor injuries.
Assistant Commissioner Matt Twist, who has overall responsibility for firearms, said he “firmly” believes police actions “prevented further loss of life”.
He added: “The first unarmed officers knew they were arriving on scene to reports of man armed with weapons and threatening to harm people inside an address.
“The officers knew there were people inside and had genuine fears for their safety.
“Armed officers were called and attempted to get the man to surrender. They entered the property and shots were fired.
“I would like to pay tribute to the bravery of all our officers who responded and thank all the emergency service staff involved.”
Neighbours said they were woken up by a burst of screaming and shouting.
Restaurant owner Akber Baloch, 52, 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.”
He added: “I was afraid about what was happening.
“I am really worried and it makes you feel insecure. I do not know who is wrong or right in this situation but it makes you feel insecure.”
IT consultant Valeria Bocanegra, 37, said: “I could hear shouting but could not hear what was being said. I could hear someone screaming and then everything became quiet.
“I think it was a man and a woman fighting.
“It is quite a shock (to hear that someone has been shot). There is a family behind this situation. A man has died and it is a horrible situation.”
Another neighbour, who did not want to be named, said the noises made her dog bark and woke her up.
She said: “It sounded to me like someone was trying to get in or maybe banging furniture.”
The woman said: “The dog was barking. There was a lot of shouting. There were lots of voices.
“You can see this sort of stuff on TV but when you see it is real and it is real people’s lives – it is just really sad.
“It is going to be really traumatic for the people who were inside.”
Forensics officers could be seen working next to a white tent which had been set up behind a police cordon.
Police tape, guarded by uniformed officers, blocked the winding roads around the scene which is surrounded by residential flats and terraced houses.
Uniformed officers could also be seen patrolling the area.
Detective Chief Superintendent Seb Adjei-Addoh, responsible for policing 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.”
IPOC regional director Mel Palmer said: “Our thoughts are with all of those affected by this tragic incident.
“The man’s next of kin have been informed and, in due course, we will be contacting them to explain our role. We will keep them regularly updated throughout our investigation.
“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.”
The coroner has been notified and a post-mortem examination will take place in due course.
Fatal police shootings are relatively rare in the UK – there were only three in the year to March 31 2023.
The most recent Met fatality was the death of Giedrius Vasiljevas, 40, who was shot at his home in Dagenham, east London, in November after calling 999 to say he had loaded guns and wanted to take his own life.