A year of bloodshed on the streets of London was rounded off by the dramatic arrest of 39 people in connection with a stabbing on Monday.

Police took the unusual step of detaining dozens of suspects at a house party in the early hours of New Year’s Eve, after being met with a wall of silence about the attack, which happened nearby.

It was thought several assailants had chased and knifed a man outside a branch of Sainsbury’s, before running to the flat on Greyhound Road, Hammersmith, which was yards away.

The victim, believed to be in his mid 30s, was taken to hospital where he remained in a critical but stable condition last night.

Scotland Yard said the violence started with a “minor argument” in a shop on neighbouring Fulham Palace Road. Witnesses described seeing about 50 police officers, including dog handlers, arrive at the party at around 1am. They marched the occupants out of the building in single file and lined them up for questioning against a wall.