Armed police have stormed the headquarters of Sony Music in London after two men were stabbed during a knife fight in the staff canteen.
Scotland Yard said both men involved were arrested after the incident, when staff were seen “running screaming” from the site in Kensington.
A witness told The Independent he heard a “commotion” coming from the third-floor canteen at around 11am.
“I saw two guys who appeared to be fighting,” he added. “One man was on the floor on his back and the other one was standing over him.
“I thought he was raining punches down but I realised a few moments later that he was holding a large kitchen knife.”
The witness said the man on the floor managed to block several of the blows with his hands, before receiving a serious wound to his thigh.
“Staff were standing around shouting and trying to intervene but obviously they didn’t want to get in the way,” he added.
“There was a lot of blood, it was splattered all over the floor.”
The man said the pair - who both work in catering - were separated and the armed man was taken to the far side of the canteen by colleagues, who tried to calm him down. He also appeared to be wounded.
Staff made a makeshift bandage out of a tea towel to staunch bleeding from the attacked man’s leg, he added.
The London Ambulance Service said two men were treated for injuries, with one taken to hospital and one taken to a major trauma centre.
It was not immediately clear whether both men had been armed, or whether the alleged aggressor was injured by his own knife as the second man attempted to defend himself.
The witness said that there was no intruder in the building and the incident appeared to stem from “two guys having a falling-out – unfortunately in a kitchen where there were knives”. “It was surreal,” he added.
Another witness, who works for Sony, said they heard screaming and banging.
“There was a lot of noise and everyone panicked a bit,” he told The Independent. “I think people thought it was going to be some kind of Charlie Hebdo thing.
"It's all got blown out of proportion. You would never see this many police for a stabbing anywhere else in London.
“There were dozens of police running in with tasers, riot shields. It was all over fairly quickly."
Police officers with guns swarmed Derry Street during the incident, as a helicopter hovered overhead. They evacuated staff and blocked off the side street where it sits, opposite The Independent’s offices.
Some witnesses initially reported seeing a man with a gun entering the building, but police said no firearms were involved.
Commander Kyle Gordon, who leads the Met's Specialist Firearms Command, said: “Thankfully this was not a firearms incident, but the initial reports indicated that there had been gunfire and there may have been an active shooter on the scene.”
He said armed officers arrived at Sony's offices within eight minutes of the first call coming in.
“We have robust plans for these types of incidents to ensure our response is swift and effective,” the officer added. “My colleagues are trained to confront the danger to keep the public safe and I would like to commend them in how they responded today, in the face of what was initially thought to be an armed threat.”
London Ambulance Service paramedics attended the scene and a man was seen being taken out of the building on a stretcher. He appeared to be conscious and moving.
A spokesperson for the Metropolitan Police said officers were called at 11am.
"Officers, including firearms officers, and the London Ambulance Service attended," he added. "Evacuations took place as precaution.
"Two men were found suffering from stab injuries. They were both arrested at the scene on suspicion of causing grievous bodily harm.
"The men have been taken to hospital where they remain. Their injuries have been deemed non-life threatening.
"There is no evidence that any firearms were involved in the incident. It is not being treated as terror-related."
A London Ambulance Service spokesperson said an incident response officer, two single responders in cars and two ambulance crews were sent to the scene.
“We treated two people at the scene. We took one to hospital and one to a major trauma centre.”
A spokesperson for Sony Music confirmed there was an incident at its Derry Street resulting in the building being evacuated.
A statement added: "Two members of the catering team were involved in a violent altercation. The incident is now in the hands of the Metropolitan Police."
Additional reporting by Jessica Morgan