Witnesses have described the horrific aftermath of violence that saw three men stabbed to death in a residential street.
A fight between groups of Sikh men in Ilford, east London on Sunday evening escalated into a fatal clash, according to police.
Scaffolder Louis O'Donoghoe, 40, was watching TV when he heard screaming and shouting outside his house, in what he said sounded like a foreign language.
"It was just chaos, absolute chaos. It was like something out of a movie, horrific," Mr O'Donoghoe said of the aftermath.
He saw the ambulance service with one person, and then realised there were another two bodies, at which point he went outside to see what was going on.
"I could see it all: one (body) to the left, two at the bottom of the stairs. It was like a bad day in Bosnia. It was pretty horrific really. I've never seen anything like it to be honest. It's like something on a movie."
He said his girlfriend was left "distraught" by what happened, and he had come home from work early on Monday to be with her.
Police were called to Elmstead Road in Seven Kings on Sunday evening.
Three men died at the scene and police said they were believed to have been aged in their 20s or 30s.
Two men, aged 29 and 39, have been arrested on suspicion of murder.
While the motive was still being investigated, police have ruled out terrorism.
A wide police cordon was in place in the area near Seven Kings railway station throughout the day as forensics officers and police dogs worked at the scene.
A forensics tent was visible earlier on Monday near a stairway, which people living nearby said leads to the railway station.
The owner of Seven Kings Cars, opposite the station's main entrance, said a man with blood on his hands had approached him on Sunday evening asking for help.
The man and a passenger who had been waiting for a taxi then went towards the scene, Mr Rana added.
During a visit to the area, Mayor of London Sadiq Khan described the incident as "shocking, horrific and scary".