Police investigating the stabbing deaths of three men in Ilford believe they were involved in an altercation the previous evening that spilled out from a banqueting venue on to the street.
Detectives think there was an "ongoing dispute" between the Sikh and Hindu men involved in Sunday evening's fight.
All three were pronounced dead at the scene after a fight broke out in the east London town.
The victims were in their late 20s and early 30s.
Two men aged 29 and 39 were arrested on suspicion of murder and remain in custody.
"We now believe all those involved were known to each other and from the Sikh and Hindu community, however we are still in the process of identifying the men and working to inform their next of kin," said Detective Chief Inspector Paul Considine.
"At this early stage, I do not believe this was gang or race-related.
"But, I believe there may have been an ongoing dispute between those involved.
"We believe the five men were involved in an altercation the previous evening at Krystel Banqueting that spilled out on to the High Road."
The identities of the dead man are yet to be released as police are still formally establishing their identity and informing next of kin.
Louis O'Donoghoe, 40, 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.
He saw the ambulance service working on 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."
A police cordon was in place near Seven Kings station on Monday as forensics officers and police dogs got to work.
The owner of Seven Kings Cars said a man with blood on his hands had approached him on Sunday asking for help.
"I was shocked. He had blood on his hands and he said there were people in very poor condition," said Nadeem Rana.
Police said there would be extra police on patrol in the area and are asking anyone with information to contact the incident room on 020 8345 3865, or Crimestoppers on 0800 555 111.